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Old 01/30/2013, 05:29 PM   #26
buffalo123
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Very good thread, fear of algae equate nutrient poor , would biopellets actually be promoting coral coloration by adding nutrients?


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Old 01/31/2013, 09:37 AM   #27
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Quote:
It's important to have the food/nutrients flowing through the system.......... the end test read out has little value than to make sure I'm inside a range. The best example I can give is that if two 100g tanks read .03 the tank with 8 fish to feed will have better colors than the same .03 tank with 2 fish.
Very accurate. And I think "nutrient throughput" or "nutrient flux" is what you are trying to describe. Natural reefs have the highest flux, with massive input coming from phyto -> microbes -> zooplankton, and massive export from a combination of phyto and macro growth. The export is so large that the "standing stock" or ambient values of N and P are very low. But if N and P were visible and you could see their "flux", it would look like a hurricane.

The percentage of macro consumption of nutrients on reefs is about 50/50 at 5 meters, I believe. Shallower, and macro consumes more; deeper, and phyto consumes more.


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Old 01/31/2013, 09:48 AM   #28
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Tagging along


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Old 01/31/2013, 09:52 AM   #29
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i would say that the massive export comes from the outgoing tides and the periodic storms.

while it is important to have nutrients flowing through the system, it is important to know the difference between organically bound phosphates and water soluble phosphates. not all phosphates are created equal and talking about phosphates without differentiating just makes this hobby even more confusing than it is already. we provide the organically bound phosphates in the food we provide, a controllable phosphate source that is nutritionally controlled by us. these phosphates are not testable with hobby equipment. what we want to eliminate and what all of these discussions about phosphate really talk about is water soluble inorganic phosphates. these are what cause algae/cyano growth. obviously these are not what we need. one must know the phosphate cycle to get an understanding on where these come from, and it is not as simple as just saying feed less. yes, this does work, but you are starving the organisms in the system of much needed fresh organically bound phosphates and other organic building blocks and hoping that they find enough food through leftovers and from eating poo from other organisms. not very appetizing. if we look at the phosphate cycle we can see that if we remove the waste products from living organisms, and any left over food, we disrupt the phosphate cycle and significantly remove the ability of bacteria from decomposing this organic material and releasing the bound phosphate into water soluble inorganic form for use by other bacteria and algae.

follow the phosphate cycle and see what make the most sense in how to eliminate the production of the unwanted phosphates, but still supply the beneficial phosphates.

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Old 01/31/2013, 10:39 AM   #30
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Originally Posted by Reefin' Dude View Post
follow the phosphate cycle and see what make the most sense in how to eliminate the production of the unwanted phosphates, but still supply the beneficial phosphates.
Can you please explain your point as it relates to the OP's original assertion (see below), the subject of the thread? The water's getting pretty deep in here, and I'm missing it...

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There appears to be: in a nutshell, assuming you use intense lighting, you can usually get away with a higher Alk level if you also have PO4 and/or NO3.
If you have very low nutrients, then it will usually give you best results with a natural Alk level 7-8 DKH. Nothing is 100% true, but from what I have found, I will bet on this idea more than any magic bottle in producing good results.



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Old 01/31/2013, 12:29 PM   #31
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My tank is ULN because my bioload is very low only having 2 clowns and 1 firefish. Since I've pulled my Alkalinity down, all my corals are starting to get their color back. I did also drop photo period significantly, but I'm considering adding about 30-60 minutes each week to the time all 4 bulbs run.

My Alkalinity is hovering around 8 - 8.2dkh but I would like to get that down even further, maybe in the 7.5dkh range.

Good thread though and I think right on target.


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Old 01/31/2013, 02:03 PM   #32
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Originally Posted by scolley View Post
Can you please explain your point as it relates to the OP's original assertion (see below), the subject of the thread? The water's getting pretty deep in here, and I'm missing it...
Maybe I can help. I'm not trying to speak for Reefin Dude, but check the title of the thread.

"the secret to colorful,healthy corals....obvious to some,elusive to many"

In the opinion of many hobbyists, including myself, supplying organically bound phosphate, while maintaining very low inorganic phosphate levels, is one of the major influences that determine a corals health and color. So, Reefin' Dude's statement was right on topic.


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Old 01/31/2013, 02:31 PM   #33
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Thanks! I follow on the concept of lots of organically bound phosphates, with low inorganic phosphates as an objective.

So is the point here that the OP's original assertions related to alk levels and high/low nutrients is incorrect? That instead the secret of "colorful, healthy corals" is lots of organically bound phosphates, with low inorganic phosphates?


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Old 01/31/2013, 09:11 PM   #34
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In my own observations, when my phosphates are high enough to get a considerable amount of algae I get little to no coral growth from sps, and even slow growth with lps. At the moment that is the case and my phosphate is reading .04 mq/l


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Old 02/01/2013, 08:32 AM   #35
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Originally Posted by SantaMonica View Post
Natural reefs have the highest flux, with massive input coming from phyto -> microbes -> zooplankton,
Please post a link to back up this statement. Particularly the part where coral reefs have massive input coming from phyto, microbes, and zooplankton. If this were true, there would have been no need for the symbiotic relationship between coral and zooxanthellae to evolve in the first place. It is the lack, or scarcity, of plankton that drove this evolution. It would be more appropriate to say there is very little plankton, of any kind, on healthy growing coral reefs.



Quote:
and massive export from a combination of phyto and macro growth. The export is so large that the "standing stock" or ambient values of N and P are very low. But if N and P were visible and you could see their "flux", it would look like a hurricane.
Again, please post a link to back up this statement.

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The percentage of macro consumption of nutrients on reefs is about 50/50 at 5 meters, I believe. Shallower, and macro consumes more; deeper, and phyto consumes more.
I'm not sure I understand what you're trying to say here. Are you saying that macro consumes about 50% of the available nutrients on a coral reef at 5 meters? If this is indeed what you're saying, we simply can not make statements like this. Even if this were true of one reef, somewhere on the planet, it would tell us nothing of all the other reefs. Coral reefs vary greatly in the amount of macro algae they support. There is very little macro algae on healthy growing coral reefs, but it may be very abundant on coral reefs that are in decline.


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Old 02/01/2013, 10:35 AM   #36
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Quote:
Please post a link to back up this statement. Particularly the part where coral reefs have massive input coming from phyto, microbes, and zooplankton. If this were true, there would have been no need for the symbiotic relationship between coral and zooxanthellae to evolve in the first place. It is the lack, or scarcity, of plankton that drove this evolution. It would be more appropriate to say there is very little plankton, of any kind, on healthy growing coral reefs.
Broneman did a series of articles on the Foods of Reefs---

http://reefkeeping.com/issues/author/eb.php

That might help you dig it up there. It's something crazy like 10,000x the amount of food passes through reefs than we can supply in our tanks. I'm not sure if it's labled in what types of forms.

I've seen shows on NGC about the massive amounts of food forms that travels through reefs.

You could also do a google search & it shouldn't be hard to find some info as I don't think it's a rare scientific find.

Now the question is...........how much of this are the corals actually taking in, seeing that they can produce most aminos on their own with the help of the zoo? I suspect it's more feeding everything else on the reef and they all benefit from fish to the bacteria. Who gets what from who is probably a complex question in a natural reef that is dependent on each other from the apex predator "the shark" down to the bacteria.

I do know from my own personal experiences though that if the fish in your tank get enough, the corals get enough unless your fish load is verrry low.


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Old 02/01/2013, 11:42 AM   #37
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This is not an area I am yet concentrating on, but I have a question as it relates to some of the conversation and that has to do with growth vs color. So far I have read just to enough to think that these two things appear to be mutually exclusive. How does this play in this discussion? What is contributing to this as it pertains to light levels, alkalinity, and transient food in the water?


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Old 02/01/2013, 10:49 PM   #38
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The inputs and exports, although all within the same system, are some of the basics that you learn when you study marine biology (a good book is Introduction To Marine Biology, by Turner-Small). It's usually not something like a dedicated study, because it is similar to trees supplying oxygen to us, and we supply CO2 to trees. However I'll have to pay more attention to copying the text the next time I run across it in a pdf or other copy-able text.

As for nutrient-poor reefs, yes they are low in N and P, but high in food particles, especially at night. That's what the nematocysts target.

Quote:
Are you saying that macro consumes about 50% of the available nutrients on a coral reef at 5 meters? If this is indeed what you're saying, we simply can not make statements like this.
The studies say this, not me. It does vary from study to study, but at some shallower amount, macro takes over. This is one of those areas that does have lots of studies and references (due to climate change). Here is the first one I could find quickly; not what I wanted but others will have to wait...


"Community structure, biomass and productivity of epilithic algal communities on the Great Barrier Reef: Dynamics at Different Spatial Scales." Marine Ecology Progress Series, Sept 1992.


Notes for this study:

Epilithic = Algae that is attached to rocks; also known at "benthic".
Productivity = Primary Production of food = "Primary Reduction" of nutrients.
Carbon = Biomass that is alive; is not GAC.
Turnover = How fast algae is eaten by grazers, followed by new growth.


"This study provides the first quantification of variation in the structure, biomass and productivity of the Epilithic Algal Community on a number of reefs over a wide area of the Great Barrier Reef. In addition, it describes within-reef and seasonal variability of these parameters.

The Epilithic Algal Community (EAC) of coral reefs is a diverse assemblage of crustose coralline and [fleshy] turf algae growing upon coral rock. In this case, the term 'turf' refers to the multi-specific and inconspicuous association of unicellular, and short (usually less than 1 cm high), simple filamentous algae [...].

The main goal of this study was to examine the natural (in situ) variations in community structure, biomass, photosynthesis-irradiance relationship, and primary productivity of the Epilithic Algal Communities on the Great Barrier Reef (GBR). Comparisons are made between seasons, successive years, and different habitats and reefs situated across and along the continental shelf. This is an extension of a study which focused on the differences between habitats and seasons within a single reef (Davies Reef, central GBR). Data on primary production of the EAC are compared with the [roughness] and nature of the reef substratum to estimate the contribution made by the EAC to whole reef productivity.

This study was carried out along 2 major [areas] designed to give a wide geographical coverage of the Great Barrier Reef. The first of these was a central GBR cross-shelf transect comprising a reef on the inner- (Pandora), mid- (Davies) and outer-shelf (Myrmidon). General environmental and structural features of these reefs are described elsewhere. The second [area] comprised a pair of reefs on the mid- and outer-shelf at 3 latitudes; McGillivray and Yonge, Davies and Myrmidon, and Heron and One Tree Islands.

Epilithic Algal Communities covered a high proportion of the reef flats (50 to 80 percent) and reef slopes (30 to 70 percent) on the coral reefs of the north, central and southern regions of the Great Barrier Reef (GBR). Crustose coralline algae and turf algae (fine and damselfish territory types) dominated the Epilithic Algal Communities in reef flat habitats, except in the near-shore region where turf algae predominated. Turfs also dominated the EAC on reef slopes. Patches of crustose coralline algae had a higher biomass [because of the calcium], but a lower photosynthetic rate [thus less nutrient reduction] than the equivalent area of fine turf algae. The net result was that these 2 main forms of epilithic algae had comparable rates of [per unit area] productivity. The [primary] productivity of turf-dominated communities was inversely correlated with algal biomass. Epilithic Algal Communities from various reef habitats at the same depth had equal [per unit area] and biomass-specific productivity, regardless of their location on [areas] extending both across and also along the Great Barrier Reef. EAC productivity changed in a predictable manner with season (maximum in summer, minimum in winter) and depth (decreasing with depth). [...] The EAC at 10 meters on reef slopes had approximately half the [per unit area] productivity of the community on the adjacent reef flat, but the EAC from these habitats had a similar biomass-specific productivity. Productivity of the EAC per unit area of reef, which takes into account the [roughness] and coverage of reefs by the EAC in particular habitats, varied between reefs, and ranged from 150 grams carbon (per square meter, per year) on the reef flat of the near-shore reef and on all reef slopes, to 500 grams carbon (per square meter, per year) on some mid- and outer-shelf reef flats. There was no apparent latitudinal pattern of change in EAC productivity per unit area of reef. Thus, availability of the EAC, the major food resource of grazers on coral reefs, appears to correlate well with known large-scale variations in grazing activity.

For a number of reasons, the Epilithic Algal Community is thought to play an extremely important role in the [feeding] dynamics of coral reefs. Firstly, a large proportion of the net primary production within specific habitats of coral reefs is provided by the EAC. This is most clearly evident for the shallow habitats, where it has been relatively easy to measure the metabolic rates of benthic [sea floor] reef communities. However, relatively little is known about the productivity of benthic plant communities on reef slopes and in deep lagoons. Epilithic [attached to rocks] algae are intensively grazed [by fish], and in the process are maintained in a state of low biomass, but rapid turnover. In the few cases where whole reef systems have been examined, the biomass of the Epilithic Algal Community is found to be considerable due to its extensive coverage of reef surfaces (up to 80 percent in some habitats), and the high [roughness] of the reef substratum. Hence, the EAC almost certainly makes a substantial contribution to the [per unit area] productivity of most reefs. Moreover, a high proportion of the carbon [food] produced by the coral reef EAC is thought to be directly available to the reef food web via herbivorous grazers. Indeed, recent studies [in 1992] of reef flats have demonstrated that grazers consume around half of the annual net production of the EAC, with the balance presumably channeled into detrital pathways in the form of [DOC] exudates and particulate matter.

Experimental plates (8 X 8 X 2 cm) cut from the coral Porites spp. were bolted directly to the reef substratum in a haphazard manner within different reef zones. [...] Plates were left in the field for 6 to 12 months to establish a 'natural' Epilithic Algal Community.

The type and irregularity of the reef surface, at the sites where algal production was measured, were surveyed at Pandora, Myrmidon, Heron and One Tree Reefs in October 1989, and at MacGillivray and Yonge Reefs in December 1989. Reef surface type, expressed as proportional coverage by sand, and 7 functional groups of biota: fine turf, damselfish-territory turf, crustose coralline algae, encrusting brown algae, macroalgae (e.g. Halimeda spp.), hard corals and other fauna (e.g. soft corals, sponges), was quantified using line transects.

The percent cover of coral plates by the 4 major functional components of the Epilithic Algal Community (fine turfs, damselfish territory turf, crustose coralline algae, and encrusting brown algae), averaged over all seasons, was similar for the 2 reef-flat zones (4 & 7) on Davies and Myrmidon Reefs. Both turfs and coralline algae were important in these habitats, but coralline algae were more abundant on reef crests (Zone 7). Fine turf dominated (57 to 67 percent cover) and coralline algae were much less abundant (20 percent cover) in the reef-slope algal community. The reef flat on Pandora on the inner-shelf differed markedly from similar habitats on the mid- and outer-shelf reefs, in that coralline algae were rare, and 87 percent of algae was damselfish territory turf. Epilithic Algal Community structure did not vary significantly with season.

The maximum net photosynthetic rate [and reduction of nutrients] of the Epilithic Algal Communities, in both [per unit area] and biomass-specific terms, varied seasonally, with the maxima in summer and the minima in winter in all zones, on all reefs.

[Primary] production of the EAC based both on area and biomass varied strongly with season for all zones and reefs of the cross-shelf and latitudinal [areas]. Productivity was highest in summer and lowest in winter.

Thus, annual production of the EAC (without taking EAC coverage, or irregularity of the reef surface into account) is 400 grams carbon (per square meter, per year) on reef flats, and 220 on reef slopes.

The EAC (turfs plus coralline algae) covered a high proportion of the surface on all mid- and outer-shelf reefs examined. [...] In general, hard corals were the other major occupant of space on these reefs (11 to 44 percent on flats; 14 to 35 percent on slopes). Although there were some significant differences between reefs in terms of the cover of particular
types of EAC, these did not suggest any latitudinal trends, nor any consistent differences between mid- and outer-shelf reefs. The one inner-shelf reef examined in this study (Pandora Reef) was distinctive in being dominated by zooanthids (61 percent), as well as its comparatively low EAC coverage. Moreover, damselfish-territory turf dominated the EAC (75 percent) on the natural surfaces of Pandora Reef, as was observed with [the experimental] coral plates from this reef, whereas in comparable habitats on mid- and outer-shelf reefs, fine turfs and coralline algae were equally important components of the EAC. Reef flats had consistently higher cover of EAC (range: 51 to 81 percent) than the adjacent reef slopes (range: 33 to 73 percent), which had extensive areas of sand. In addition, coralline algae were important on reef flats, and filamentous algae dominated the reef slopes.

The EAC covers a high proportion of reef flats (up to 80 percent) and reef slopes (up to 50 percent) throughout the GBR. However, the extent of this cover, as well as the community structure of the EAC, varies with location, such that cover of substrata by algae is greatest on reef flats in the mid- and outer-shelf region, where the community is usually dominated by a mixture of well grazed turfs and crustose coralline algae.

Large fleshy algae (e.g. Sargassum spp.), which are usually relatively rare in all habitats on the mid- and outer-shelf reefs, dominate in some seasons and habitats on inner-shelf reefs. Although large fleshy algae were not common in the study site at Pandora Reef, the adjacent windward edge of this reef has an extensive Sargassum community. The transition from an algal community, comprising mainly coralline and low turfs on reefs of the mid- and outer-shelf, to one characterized by lush turfs and large fleshy algae, correlates with a significant decrease in grazing intensity.

[Maximum per unit area] productivity occurs in summer in shallow habitats, and minimum productivity occurs in winter on the reef slope.

In shallow reef areas, EAC biomass is lowest [i.e., highest grazing and primary production regrowth] in summer, and peaks around winter, whereas at 10 meters on the reef slope, biomass is lower than on the reef flat, and it is seasonally stable. The seasonal variation in biomass of EAC on the reef flat can be explained by the seasonal changes in grazing intensity relative to productivity. While variations in productivity and grazing intensity are positively correlated, the magnitude of seasonal change in rate of grazing on algae exceeds that produced, thus resulting in the observed seasonal fluctuations in biomass. On the reef slope, presumably EAC productivity and losses, such as those due to grazing, are in balance over the year. Similarly, [previous researchers] observed that epilithic algal biomass decreased towards summer on the reef flat at One Tree Island, and that this corresponded with an increase in grazing activity. The lower biomass of the EAC on the reef slope compared with the reef flat is in part due to the difference in [algal] community structure; reef slopes are dominated by turfs (80 percent cover), which have a lower biomass per unit area than coralline algae [due to the calcium].

It is now well established [in 1992] that the EAC represents an extremely important trophic [food] resource on coral reefs through the interaction with grazers. In turn, grazers exercise a strong influence on the biomass and community structure of reef algal communities. Grazing activity, within certain limits, is also thought to stimulate productivity of epilithic algae by selecting for fast growing forms of algae [and thus the most "primary reduction" of nutrients], the removal of [dying] material, and an enhanced availability of [food]. Over an entire reef flat, it has been estimated that grazers account for [consuming] 40 to 70 percent of EAC net production, but there is considerable spatial variability in grazing intensity. For example, grazing rates are highest on the outer shallow reef crests and slopes, and lowest in leeward edges of reef flats and in lagoons. On a larger scale, the abundance of herbivorous fishes (the major grazers on the GBR), and the rate of removal of the EAC by grazers (determined by grazer exclusion experiments) is much higher on mid- and outer-shelf reefs than on reefs near-shore. These differences in grazing pressure within reefs, and between reefs located across the GBR, do not influence the rate of turnover of the epilithic algae (i.e. that established on our [experimental] coral plates) being grazed. For example, algal communities from different habitats at the same depth on Davies Reef are equally productive. Furthermore, the EAC on Pandora Reef was as productive per unit area and per unit biomass as the communities on Myrmidon and Davies Reefs.

The rate of EAC [primary] production per unit area of reef surface, or actual algal food availability (i.e. the [per unit area] production of EAC on [our experimental] coral plates, corrected for the irregularity and algal coverage of reef surfaces), does however correlate with the rate at which algae are removed by grazers, as was demonstrated in the comparison between reef-flat habitats on Davies Reef. Similarly, in considering the cross-shelf gradient, the availability of algal food resources on Davies and Myrmidon Reefs (400 to 500 grams carbon per square meter, per year) is 3 times that of Pandora Reef (160 grams). This compares with a 3- to 5-fold differential in abundance of grazers on these 2 groups of reefs. These differences in algal food availability between sites are due to differences in algal coverage of reef surfaces. [Previous researchers] estimated grazing rate at 0.1 grams carbon (per square meter, per day) on Pandora Reef, and 0.6 on the mid- and outer-shelf reefs. Hence, grazing accounts for 23 percent of the EAC net production on Pandora Reef and approximately 50 percent of the production on the reefs offshore. This is in close agreement with independent estimates of the average annual grazing impact on the EAC at Davies Reef (57 percent) and on One Tree Island (50 percent). It remains unknown, as pointed out by [a previous researcher], whether grazer abundance controls algal food availability, or vice versa."


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Old 02/02/2013, 06:01 AM   #39
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A truly awesome amount of information which just on the surface would appear to aid in many areas of reef keeping. My inner geek is in information overflow. Aside from getting a handle on the topic of the current conversation, it would also help those of us trying to get a handle on workings of various biotopes.

Would you post the link to this study? Or, was this in the book you mentioned?


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Old 02/02/2013, 08:23 AM   #40
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Originally Posted by keithhays View Post
A truly awesome amount of information which just on the surface would appear to aid in many areas of reef keeping. My inner geek is in information overflow. Aside from getting a handle on the topic of the current conversation, it would also help those of us trying to get a handle on workings of various biotopes.

Would you post the link to this study? Or, was this in the book you mentioned?
Here's the link. https://www.google.com/url?sa=t&rct=...41867550,d.eWU


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Old 02/03/2013, 09:29 PM   #41
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Interesting topic! Good reading!


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Old 02/04/2013, 03:39 PM   #42
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another interesting article about algae and coral dynamics.

Effects of live coral, epilithic algal communities and substrate type on algal recruitment

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Old 02/04/2013, 05:35 PM   #43
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Thanks, forgot the link. That's what happens when I rush.


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Old 02/05/2013, 11:22 AM   #44
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Originally Posted by Reefin' Dude View Post
kevensquint- during your research did you also note how long the TOTM had been setup and the depth of the substrate?

phosphates in food is a whole lot different than water soluble phosphates. we can only test for the latter. in general the more you feed, the more water soluble phosphates that will eventually get in the water column. SPS corals need organically bound phosphates, and not water soluble phosphates. if you feed your fish more, more organically bound phosphates will be taken up by the corals, better color, better growth. those that have problems tend to not feed enough and not export enough. it is easy to starve corals when worrying about phosphates. we all look at our test kits, or see the algae, so we feed less thinking that we are lowering the phosphates. we are just lowering the amount of phosphates going into the coral animal, feeding it. we are still maintaining the phosphates going into the zoax (those that show up on our test kits), which does not help the corals themselves.

G~
So in essence, you are saying in this situation you would need to export more?

(I love this thread already, but I would like to hear more about the relationships between alk/light/and P & N levels.)




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Old 02/05/2013, 03:20 PM   #45
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if one is wanting to keep oligotrophic organisms, then the answer is always export more. you are removing the inorganic phosphates. you then will need to make sure everything is well fed, so you must feed more. organically bound phosphates.

we are talking hermatypic corals here. the nutrients are tightly traded between the coral and zoax. the coral brings in the food from normal feeding. its wastes then feed the hoax, which it is really in need of the inorganic phosphates, plus CO2. this in turn provides the coral some organically bound phosphates as food plus O2 for respiration. this is quite simplified, but gives the solid basics. light comes into play with population control due to phosphate levels and also the coral trying to control the amount of O2 production by the zoax. the pretty colors we see are blocking, or in some cases amplifying the light for zoax use. i need to see if i can find the corresponding thread about this on RC, if it still exists. it would have been from 2005.

G~


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Old 02/11/2013, 08:16 AM   #46
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I'm going to test this out and see what happens. I always have low PO4 and NO3 and was running my Alk around 9. My coral colors are pretty much all washed out.

I am slowly bringing it down to around 7.8 in order to see if there truly is a correlation. Should be interesting. I guess I should take some before/after pics?


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Old 02/11/2013, 12:12 PM   #47
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Originally Posted by csauer52 View Post
I'm going to test this out and see what happens. I always have low PO4 and NO3 and was running my Alk around 9. My coral colors are pretty much all washed out.

I am slowly bringing it down to around 7.8 in order to see if there truly is a correlation. Should be interesting. I guess I should take some before/after pics?
While lowering the alkalinity from 9 to ~8 dKh may help somewhat with coloration, pale colored corals typically indicate a lack of nutrients via feeding. I have tested this out by going fishless in a system with no external feeding. Within a few months the SPS corals had paled noticeably. I then fed the tank as if fish were present and they recovered their original coloration. This was with an alkalinity of ~10 dKh.

The key is to feed adequately to supply nutrients to the coral, but also effectively remove the waste products (especially inorganic phosphate) via detritus removal, skimming, GFO, etc. If inorganic PO4 is not dealt with, coral growth/health will be compromised and algae will proliferate.


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Old 02/11/2013, 12:13 PM   #48
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awesome read!
i was using API to test my nitrates until today. here are my readings:

salinity: 1.026 refractometer
PH: 7.9-8.2 (depending on time of day) milwaukee PH montior
NO3: 0 salifert
PO4:.02 hanna low range meter
MG: 1300 ELOS
CAL: 420 salifert
ALK: 8.3-9.0 salfiert
temp: 78.5 itemp on reefkeeper lite
SO, i guess im going to drop my alk down to 7.5 and see what happens. the reason for my swing is because i can only dose once at night (work). i have 2 drews dosers in the mail as we speak to fix this, along with my reefkeeper lite.


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Old 02/11/2013, 04:06 PM   #49
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It's been said that well fed corals, like natural corals, are generally darker.


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Old 02/12/2013, 07:40 AM   #50
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Originally Posted by Nano sapiens View Post
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The key is to feed adequately to supply nutrients to the coral, but also effectively remove the waste products (especially inorganic phosphate) via detritus removal, skimming, GFO, etc.
Well I think that's the toughest piece of the equation. How do you find what those levels are? I have a 150 with ~ 50 SPS frags, most are 1"-2" in size. How much should you feed? My fish load is low:

1 Vlamingi
1 PBT
1 Purple Tang
1 6 line wrasse
1 blue chromis
1 orchid dottyback

How should you approach feeding? How much, what, how frequently etc?


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