miracle-grow for sw planted tank to increase phosphates and nitrates

[estrange]

I found a bottle of this stuff in my garage and looking at the ingrediants it looks like its good for macros.

http://www.miraclegro.com/index.cfm/...5936ae9a153f2b

Has anyone tried this? I've been having stagnant growth due to problems keeping nitrates up. Will this be enough to increase nitrates iin a 15 gallon tank macro tank?

[Samala]

Here's the problem I have with using Miracle gro.

Nearly all plants and algae use up the nutrients of nitrogen, phosphorus and potassium. When you see fertilizers you see this listed, as in miracle grow, as a ratio of 8-7-6. So for every 8 molecules of nitrogen available, there's 7 phosphate and 6 potassium. Miracle gro was formulated for use with vascular land plants, and this ratio seems to do pretty well for them.

But it wont be too great for your macro, or seagrass. Lets throwout potassium as an issue for the moment since I dont know either way if potassium is used up by underwater marine vascular plants or not. (I have strong reason to believe that it IS in fact needed, but we wont go that far for this post.) Suffice to say that potassium is not mentioned for macroalgae, or phytoplankton growth.

So what's wrong with miracle gro? The ratio of the nutrients as they're being provided is all wrong. I am finding that macro and seagrass lean more towards a ratio of 16:1 in terms of nitrogen and phosphorus. Every sixteen nitrogens they use up, they use just one phosphorus, on average. Notice that in miracle gro, when the macro's use up 16 nitrogen's, they are only taking up one of the 14 available phosphorus.

That leads to a serious overload of phosphate in the system, and causes all sorts of headaches if you cant export it in another way.

While it would certainly increase you nitrates in a 15gallon, it will seriously skyrocket the phosphates too.

My advice? Look for Seachem's Fluorish Nitrogen, its made for the freshwater planted crowd, but I find that it works very well for me in my seagrass tanks.

Also.. test the phosphate and nitrate levels in your tank. You may not need to add either, and we could be dealing with another limiting nutrient.. not just nitrate. Some reported other limiting nutrients can be magnesium, calcium and iron. I find of the three that iron can make a real difference.. but I dont recommend adding anything unless you're testing for it. Its too easy to over fertilize.

Any more q's fire away! I'm excited that more people are willing to experiment a little with adding in some nutrients to their tanks for the benefit of their macro.

>Sarah

[DrBDC]

What about KNO3? I have some that I started to mess with on a freshwater planted. I ran into such a greenwater problem I removed half the lights and quit fertilizing. I should have built that one from the ground up with correct substrate but I just started with playsand (reg type) and then decided to go planted. I may have been too weak in the CO2 with a DIY system too. But that's another story. I had bought Greg Watsons pre-mix and was using that but I also have plain old saltpeter.

I have tested my water and show no nitrates and my cheato is looking kind of rough and breaking off alot. It was growing like crazy but I improved my DIY skimmer with a whitewater air pump and a half dozen of those ceramic 6" round stones and a few time it wasn't set right and I did some 30 gallon super-wet skims. Even set back at a good level I can't get any nitrates for the macro.

[Samala]

KNO3 is a great alternative to the bottled stuff. But I find that reefers seem a little less hesitant if I suggest a product made for aquaria (even if it is freshwater) than a chemical that is used for so many different uses.. ie. stump remover (!).

I have used KNO3 on my system, and will most likely switch back to it in the future since I have a stable source from it. gregwatson.com is a great source for other DIY'rs.

If you are only growing macroalgae you might consider switching to another nitrate salt.. such as Sodium nitrate (NaNO3) or calcium nitrate (CaNO3). The potassium in the other salt might not be necessary for the algaes. While I'm not sold that a buildup of potassium does any real harm, I think the other two alternatives are a better idea if you have a lot of money invested in the tank. I would hate for someone to lose coral or inverts or something else because I told them potassium wasn't potentially toxic or harmful.

If you've got seagrass, you can join me in the fun of trying to determine if they are using up the potassium from the mix or not. Since its hard to measure potassium in water samples.. its been an interesting ride to figure this out.

Either way, if you feel adventurous, you can use it. I think that's what I'm saying.

The mix from Greg.. I'm not really familiar with it. But it will certainly be using potassium phosphate and potassium nitrate. So once again, you could potentially be adding too much potassium, among other things. The only all-in-one fertilizer I was pondering for people to use was Guillard's formula for phytoplankton (F/2). That is at least more in line with algae's needs, and closer to the seagrass nutrient uptake profile.

Oh yes.. greenwater problems in freshwater usually indicates an ammonia or nitrite problem. CO2 could also have been working in that equation to make a bloom.. but usually greenwater is from an overblown biological filter that can't keep up or a cycling tank. IME at least.

>Sarah

[estrange]

Thanks for such an indepth response!

My nitrate levels have always been undetectable along with phosphorus. This was probably why I get no growth. After adding the miracle growth I was able to jump the nitrate to 10ppm. I will check tommorow to see how much of it will be removed by the macros.

I won't mind the nuisance algae as long as it doesn't affect my macros.

I'm also curious on the affects of potassium in macros. I have the advantage in going a little crazy on the dosing because I don't have much to lose. The tank is not hooked up to anything. It's just macros, no LR or LS.

I'm going to set up a 5 gallon and dose with a stump remover.

[DrBDC]

I'm going to do it too as soon as I go buy a new nitrate test. It's a little scary to add nitrate and I want to make sure I'm not reading it wrong or my test is old and bad.

[Samala]

Estrange.. if possible try measuring your phosphate level along with the nitrate. It may be REALLY high if you used miracle gro.. I'm interested in knowing just how high it could be. (2, 5, 7 ppm or more?)

I am in the same situation you are.. the tank is just macro/grass with very little to lose (Astrea snails) but I wont be able to do as much tinkering when the seahorses come out of quarantine in late September, so I'm trying to get in my last crazy ideas now.

I really dont know if potassium is going to do anything for the macros.. its not found in Guillards formula at all.. so phytoplankton (reds, greens and diatoms) dont use it. I havent found a paper yet that reported on the machinery involved in potassium uptake in macroalgae or phytoplankton. Doesnt mean they're not there of course. Keep me posted both of you!

>Sarah

[DrBDC]

I'm not sure if this info is any help but I grow my own phyto using a 2 1/2 gallon jug that I mix my salt to 1.020 and then add 2 tablespoons of standard miracle grow (the crystal version not the liquid). I use that as my medium for nanno culture. Then when I harvest I'm adding a 2 liter of it over about a 4 day period. I haven't had any problems from this in the 3 months I've been doing it. If the phyto isn't eating the potassium then it would still be in the solution. It hasn't brought my nitrates up any and my cheato is still starving off. I'm giving some away today to see if that helps a little. So I guess this week I need a phosphate and a new nitrate test.

FWIW

[Plantbrain]

MG has NH4, not just NO3..........and urea.

Try dosing NH4 and urea alone..............
See what happens:-)

I do not suggest it.............

If you add small tiny amounts, you can get away with it or do daily water changes(large ones).

Regards,
Tom Barr

[anabolic_1]

This thread was started as "SW PLANTED TANKS" was that a typo or did I miss something?


Mike.

[Plantbrain]

Originally posted by anabolic_1
This thread was started as "SW PLANTED TANKS" was that a typo or did I miss something?


Mike.

We are talking about marine plants/macro algae............not sure why you say this..........

Adding NH4+ to a marine tank is very dangerous due to the pH NH4/NH3 issue, at higher pH's the NH4+ converts mainly to NH3 which is more more toxic to life. I tried it. I do not recommend it ever.

Table 1. Un-ionized NH3 as a percent of total ammonia (by temperature and pH).
_________________________________________________________
Percent NH3 of total ammonia
_________________________________________________________
Temp pH
(F)
6.5 7.0 7.5 8.0 8.5
___________________________________________________________
68 .13 .40 1.24 8.82 11.2
77 .18 .57 1.77 5.38 15.3
82 .22 .70 2.17 6.56 18.2
86 .26 .80 2.48 7.46 20.3

NH3 is much more dependent on pH than temperature. Within the pH range shown, an increase of one pH unit will increase the NH3 concentration about 10-fold.

What is VERY important is the relative toxicity of NH3 and NH4+ at
different pH.

The next table shows that small concentrations of both ammonIA (NH3) and
ammonIUM (NH4), or the total of both, can be fatal to the animals in a tank.

Table 2.Lethal ammonia concentrations at 86 degrees F.
(by pH, and duration of exposure)

pH duration Lethal* Ammonia Concentration (mg/l)

total NH3
______________

6.5 1-hr 14.3 0.036
4-day 0.73 0.002

7.0 1-hr 11.6 0.093
4-day 0.74 0.006

7.5 1-hr 7.3 0.181
4-day 0.74 0.019

8.0 1-hr 3.5 0.26
4-day 0.47 0.035

8.5 1-hr 1.3 0.26
4-day 0.17 0.035


*Lethal concetrations are derived from levels at which half of the exposed
individuals die.

High K+ will not impact macros, I've used it extensively.

Samala, I have a paper coming out in about a week on K+, but mainly on FW macrophytes, there are a number of K+ studies done, few though on the marine side............
I'll let you know later on the marine papers I've found on K+ trasportors.


Regards,
Tom Barr

[Seahorsewisprer]

I am concerned about the effect of potassium on fish and corals. I am using my planted tank to "filter" my reef and FO tanks, trying to get away from using phosphate adsorbers.

I work in people medicine, and high K+ levels in people are extremely toxic. But, do fish react to high K+ in their environment? Could they absorb it osmotically? Do their little kidneys regulate it like our big ones do?

I just wish I could test for it!

[Plantbrain]

Think about high Na+ levels and the relative influence of osmotic shock vs a salt solution as concentrated as seawater.

K+ at another 50ppm+ etc is not going to cause much issue.
You can also test this independently of NO3, use either KCL or K2SO4(or try both independently).

Think about evaporational losses in SW tanks and how much salt pressure is going on there in terms of ppm vs the ppt changes.

I think total salt content is more an issue, a little extra K+ is not going to influence anything from what I've seen.

But I also do not keep SPS corals and many common reef critters etc.


Regards,
Tom Barr

[Samala]

Tom... where is your paper coming out? Plant Phys? Aquatic Bot? Lemme know.. I will definitely be on the lookout for it.. we are considering jumping into nutrient dynamics, gene expression, etc etc in diatoms (ok, its a jump, but I'm reading EVERYTHING at the moment.. plus it's cool for my tanks).

>Sarah

[Plantbrain]

My site:

www.BarrReport.com

I write a monthly review hobbyist article on each nutrient, light, DOC, DIC, Nitrogen, PO4, Trace metals, etc, etc.

I have about 25 topics, and roughly 30 or so articles lined up and it's started back in Jan 1st.

This month is K+.

Some may end up in a journal later but a book is much more what I am seeking to do and this web site allows me to do that with some degree of steadiness.........otherwise it'll never get done

I have perhaps another 15-20 articles on marine plants in the web mag, it's pretty heavy reading for a hobbyist.

I know the editors at AB and JAPM, and I kill weeds.
That will be maininly where you will see any papers done by me, I have at least 6-8 that need done right now:-)

Well, I'll see what I can get out later this fall.
When yoyu write for yourself for a book and each month, plus write for the main job, well, you get the idea........fried.....haha

Regards,
Tom Barr

[Fredfish]

Dang, go away on holidays and you miss all the good posts! Can't believe it took me so long to find this thread.

The only all-in-one fertilizer I was pondering for people to use was Guillard's formula for phytoplankton (F/2). That is at least more in line with algae's needs, and closer to the seagrass nutrient uptake profile.

Funny, I have been pondering why my macro algae has stalled despite my nitrate additions. All this time have had two part f2 sitting in my fridge, a multi-year supply for growing phyto.

I have wondered the same thing. You can just buy the micronutrient part of the formula either in liquid form (Aquatic Ecosystems) or in powder form (Florida Aqua Farms). The liquid is missing the b12 and biotin 'cause thats in with the nitrates and phosphates, but in the faf formula only the nitrate and phosphate are left out of the dry mix.

My question is, how much to dose? about 3 drops will do me for 2l of phyto, but thats not much biomass compared to macro.

I just dumped a couple of capfulls of part a to see what happens.

Fred.

[Samala]

Fred.. I think I'm converting you to dummy science.. ask a question of yourself.. say "hey, what could the worst be, I trash my tank and start over again.." and then just let the fun begin. So you dumped in a few capfuls of part A.. what precisely is in part A? All my cool AqEco catalogs are at the lab with the zebrafishies..

Oooh ooh oooh, are you dosing iron? Or is that in the part A? Do you have any fun nuisance algae popping up, or just the slow macro growth?

>Sarah

[Fredfish]

First off, as my history of economics professor pointed out so long ago, the Brittish empire was built on the backs of a nation of prictical tinkerers. We are not dummy scientists.

Part A :
Iron .4%
Manganeze .034%
Zinc .0037%
Cobalt .002%
Copper .0017%
Molybdenum .0009%

Its missing b1 b12 and biotin, which are in part B along with the nitrate and phosphate.

I wonder what the places that grow macro algaes use for a fertilizer?

Do I have any nuisance algae. Well, its a peculiar thing. My main tank is full of cyanobacteria (a little patch of which turned a really cool fluorescent highlighter pink for a few hours the other day), the other is growing benthic diatoms and very slow growing macro.

Fred

[Plantbrain]

Add KNO3, say 5ppm.
I bet you are near zero now.

Watch your PO4 and plant health for the next 3 days.
Cyano should be on the ropes by a week.

Regards,
Tom Barr

[estrange]

Okay, miracle grow was a pretty bad idea. Couple days after I added the macros began turning white. I'm not quite sure why this happened. My guess is the ammoniacal nitrogen in the mixture. I think plantbrain is right about the MG4. A gardener told me that this form of nitrogen if dosed improperly can burn plants. But this is a marine plant so his statement might or might not hold true. I did a 100% water changed and the macros are starting to grow again.


What do you guys think about this?

http://cgi.ebay.com/Potassium-Nitrat...QQcmdZViewItem


I can't believe plants are harder to grow than corals. I never had issues with getting good growth with corals. I'm still clueless on what it takes to grow macros. I know nitrate and phosphate are key, but my macros grew right after my water change, which should have meant nitrates and phosphates were very low.

I'm also curious on what the algae vendors use to grow these suckers.

Hey plant, which UC do you research at?

[Samala]

I'm really shocked ebay allows that sort of auction.. saltpeter is highly, HIGHLY regulated here at my university for several reasons. You have to practically give them a DNA sample in order to get even a kilo of it.. which is about as much as they are selling on that auction. 900g of this will go a long way and last a long long time. Not that there is a real shelf-life crises with this, but you might want to check out gregwatson.com and compare amounts/prices/etc.

I dont think the plants are harder than coral, you just have to reset your head and get used to playing by some new rules. And with coral, since its so well established, people have a good general sense of what is right, whats off, whats going on general. We're not there yet with seagrass/macro growing.

I think most of the algae vendors simply use circulating salt systems to grow their products. I think most are situated on the coasts for this reason.

>Sarah

[DrBDC]

You can find it at most the lawn and garden shops. I got my last bottle at Medicine & More for 4.83 for 4 grams on a shelf. That's too much to pay buying that way though. And if you have teenagers you can slip it into their food.

[modemfox]

Saltpeter is regualated because you can make bombs out of it... Please don't ask how i know.

[Samala]

Hehehe.. modemfox.. I was going to say but held back because I'm already in trouble (most likely) for mentioning the US/Canada border a few threads back. Lol. Homeland security will now be adding your name to the blacklist. Expect to get hauled over to the bad-people lane at the airport... I ALWAYS do (over eighteen flights since 9/11.. sigh.. all of them I've been all but strip searched). Someday I pray people will look at my last name and not freak out.

>Sarah

[Plantbrain]

Originally posted by estrange I did a 100% water changed and the macros are starting to grow again.
What do you guys think about this?
I can't believe plants are harder to grow than corals.

Yes, they are in some ways.
KNO3 can be brought as well as KH2PO4 etc from www.gregwatson.com for cheap and will last you likely a lifetime for 2lbs or KNO3, 1/2 lb of the PO4.

add only KNO3, do not add anything with NH4 other than fish/invert critter bioload.

I never had issues with getting good growth with corals. I'm still clueless on what it takes to grow macros. I know nitrate and phosphate are key, but my macros grew right after my water change, which should have meant nitrates and phosphates were very low.

I'm also curious on what the algae vendors use to grow these suckers.

Hey plant, which UC do you research at? [/B]

The macros need good alk and Ca++ and also good aeration.
corals and macro's love water changes, bigger the better.

But if you dosed some KNO3, KH2PO4, traces back right afterwards, then it will do even better.

Ca
Alk
NO3
PO4
Traces
Aeration

UC Davis

Regards,
Tom Barr