Algae Scrubber Basics

[sensei]

Originally Posted by sensei

I will be cycling my new 470g DT soon. I will seed that tank with bacteria loaded ceramic rings and add bacteria solution in a bottle. I have read that cycle should be completed in around 3 days. after that I will be adding fish slowly.
questions :
when should I install the algae scrubber??
should I put it in the sump since day 1?
I ask because at the begining there will not be much nutrients in water and I dont know if it good or not to start cycling a tank with an ATS installed??
I guess I should dose some food since day 1 to feed the bacteria and kick the cycle??

Originally Posted by Floyd R Turbo

Yes, it won't hurt anything to start it on day 1, but like you said, you just might not get a lot of growth. You will likely get a brown diatom coating, and the screen will start to get some calcification, so these are good initial stages that you would have to go through anyways, so the earlier, the better. Then, when you start to add some livestock and get some biodiversity going, the screen will start to react a little more quickly, vs if you waiting until you have some nutrients and then start the process.

You can always use a short photoperiod and a lower flow rate to start up the screen. So maybe 50-75 of the flow you would normally run it at, and then just a few hours/day of light.

Floyd,
above you say that it is better to start the scrubber from day 1 in a new DT, I am just a little worried that if I run it from day 1, the scrubber will consume most available N and P from water, so to lower the capacity of scrubber I could run it from day 1 at a flow of 20GPH / inch and only light the screen 6 hours??

do you think this is a good idea? please tell me what you think

how much time does a new ATS needs to be running to go through the initial steps and be ready to work at full capacity?

can I know which are the initial steps that the ATS has to go through?

Thanks

[karimwassef]

Ok. Set up my "end to end weir overflow scrubber"

I didn't realize this stuff floats. I let it float but we'll see if that's the best solution.

It's 5" wide x 5' long. I zip tied 5 sheets that I roughed up with a hole saw drill bit. I used pex tube to get smaller than a 1/2" PVC.



Here's the view of the whole thing submerged/floating. The three halides are overhead provide a lot of direct light.


Left side




Right side




Top views:
Left


Right


Cleaning up the section here was a bit of mess. Lots of coralline, hair algae, snails, crabs, pods, starfish, even anemonae.

We'll call today day 1 of the weir scrubber experiment. Flow varies from steady state 4000gph to a surge variance between 2000gph and 8000gph. Not all that flow moves over the sheet since only 5' out of the total 8' is covered. But it experiences flow in two directions: once in the overflow direction and another from left to right since the main overflow pipe is on the far right, so all the flow from the rest of the weir has to cross to get to the right.

[salty joe]

I predict you have a winner! And no additional energy cost is sweet.

[Floyd R Turbo]

Karimwassef, look back at post 7106

[karimwassef]

I like the mortar idea for accelerating getting the scrubber online. I only have narrow windows of time to get some of these projects done before I need to travel or address other responsibilities, and I'm ok waiting for the algae to take hold gradually.

Haha- just realized that I said "I have more patience than I have time". Don't even have a word for that? Not really irony?

[karimwassef]

The mortar should make it sink too. I'll see if this works. If not, I'll mortar it.

[james30ct]

I have a 180g mixed reef with 3 tangs. I bought a 200gph pump and have it on a 12x10" screen. Im going to do 27k cfls at first and may change to leds. Should I light bith sides of the screen?

[Floyd R Turbo]

Is 200GPH what you meant or is that a typo?

You need actual flow (after head loss) closer to 35 GPH per inch of screen width, so if you have it on a 10" wide screen, 350 GPH with about 36" of head.

You're looking at something more like 500 or 600 GPH at zero head in order to get 350 across the screen.

I would light both sides of the screen, but the first thing I would review is the screen size, 10x12 is big enough (when lit properly) for 10 cubes/day of feeding. If your lights are smaller than what they would need to be for the screen size, then you can reduce the screen size to match the lighting (and that might reduce your flow requirement a bit)

[SantaMonica]

So what kind of algae is this growing on the scrubbers?

Once it grows green, it's usually Cladophora, and if it growing fast it's usually Ulva Fasciata, sometimes with with Ulva Lactuca.

Also, is there anyone who ran a fuge with macro algae at one time & a scrubber at another & what was the outcome?

Many people have added a scrubber to a fuge, and the fuge macros died. After all, the scrubber thinks the macros are nuisance algae, and the stronger photosynthesis of the scrubber out-pulls the nutrients away from the macros.

Abusive methods? Can you link some?

Things like overdosed iron, and copper wires.

I'm intrigued by the mechanism by which the scrubber is providing pods and food for tangs

Simple: algae is what pods eat. And algae and pods are what tangs eat.

if a Algae scrubber can over scrub nutrients or not

No, because as nutrients get low, the scrubber slows down.

what we would call algae roots must work their way into the plastic

I think what it really does is wrap around the open grids of the screen.

What I wanted to do was to add those super small scratches in the plastic and then bigger ones and so on

This is good, just a lot of work.

Are there websites that sell premade kits?

No, it's almost the same as reading these forums and getting the parts yoursef.

can I know which are the initial steps that the ATS has to go through?

Usually slime to start, then green hair. Then maybe some corelline or lime buildup, which you can scrape off.

I didn't realize this stuff floats

Yes most screen is polypropylene, which is like the rope they use for skiing.

[salty joe]

Originally Posted by SantaMonica

Yes most screen is polypropylene, which is like the rope they use for skiing.

While polypropylene is outstanding for water immersion, it does not hold up well to UV at all. I used some for a critter guard and it got crispy in a couple three months. It was exposed to the sunlight through commercial skylights that claimed to block UV. So, if your lamps are putting out any UV, don't expect the poly to last.

[Floyd R Turbo]

The Darice #7 Mesh plastic canvas is actually Linear low-density polyethylene (LLDPE) and while I have had a screen deteriorate over time, it took well over 2.5 years and it was mainly due to aggressive scraping, combined with having 2 Royal Blues on opposing sides at full strength.

LED scrubbers have little if any UV component. Time has shown that even T5HO and CFL scrubbers (which have a UV component) do not deteriorate screens, at least, not noticeably. I'm sure that many can attest to this.

[Spar]

Bud, any thoughts as to what type of water the mortar-added sheet should be soaked in?

I am currently soaking it in RO/DI since it will have the most absorption ability.

[Floyd R Turbo]

tap water would probably be OK but RODI would probably be better as it would suck more out, or just do it faster

[Floyd R Turbo]

Originally Posted by sensei

Floyd,
above you say that it is better to start the scrubber from day 1 in a new DT, I am just a little worried that if I run it from day 1, the scrubber will consume most available N and P from water, so to lower the capacity of scrubber I could run it from day 1 at a flow of 20GPH / inch and only light the screen 6 hours??

do you think this is a good idea? please tell me what you think

You can do that, but is there a particular reason why you don't want the scrubber to keep N and P down?

Originally Posted by sensei

how much time does a new ATS needs to be running to go through the initial steps and be ready to work at full capacity?

Depends on the system. Typically this has been 4-6 weeks usually. With the mortar screen method, this might change. I haven't seen this in action personally and since it's relatively new, count on 4-6 weeks until results come in and are consistent. As with everything new, there might be a right way to make them, and a wrong way (or maybe just a "that'll do" way and a "best" way)

[Spar]

I will be running my scrubber off of a manifold coming from one my return pumps. I currently have a 3/4" nipple coming off of it. I however made the 8" slot out of 1" PVC. Am I better off changing to a 1" nipple coming off of the manifold, or will attaching 3/4" tubing to 1" PVC be just fine as long as I am pushing through the required GPH?

It will just be a pain in the rear to get the new nipple put on, but can if necessary/better.

[Floyd R Turbo]

should be fine, you will get a bit of head loss which will reduce flow through the 3/4" section but you should be able to adjust things to make it work.

[jason2459]

There's a lot of species of Cladophora
http://www.algaebase.org/search/species/

Is there a specific type of types that are more common in our aquariums ?

Here's what mine has been turning into




Kind of reminds me of chaeto.

[sporazoa]

So you guys are discovering that an algae scrubber is more efficient at removing phosphates from the water column than a sump/fuge with chaeto or other fuge algae?

Why does it have to be suspended & why not just submerged? Isn't it the same algae that grows on our rocks & fuge & comes in from reef plugs & coral rocks?

[karimwassef]

I have a fuge and I use it primarily to cultivate pods. The chaeto is ok but it is susceptible to acting like a mechanical filter and trapping waste that results in a cyano bloom (in the sump only) over the chaeto.

Maybe I wasn't pruning it often enough, but I'm experimenting with a scrubber primarily to avoid the cyano on the chaeto.

[Spar]

Originally Posted by sporazoa

So you guys are discovering that an algae scrubber is more efficient at removing phosphates from the water column than a sump/fuge with chaeto or other fuge algae?

Why does it have to be suspended & why not just submerged? Isn't it the same algae that grows on our rocks & fuge & comes in from reef plugs & coral rocks?

Copied from the other post has a great answer to that. Basically saying that exposure to air is much more efficient and effective. See below:

Originally Posted by kinnadian

The combination of very high lighting and the air/water interface of the waterfall method making an extreme abundance of CO2 available for the algae greatly promotes its growth.

The screen also allows air to pass through it to keep the base algae alive and maximises available lighting surface area.

The CO2 content under water is much less so the algae will preferentially grow on the screen.

[mattberrytr]

I don't think it has been proven that waterfall scrubbers are so effective because the algae growth is pulling CO2 from the air. Personally I don't think this happens for any scrubber method - be it upflow, waterfall or even most surge scrubbers. The algae would have to be exposed to the air for a while before it's dry enough to absorb any CO2. It's much more likely, IMO, that the speed at which the water is flowing over the algae growth is allowing more nutrients to be absorbed by the algae.

When scrubbers operate submerged, they are usually in a sump, or an area of much lower flow. Even in a sump that has very high flow running through it, it's likely that the flow rate very close to the algae (which is what is important) is significantly slower than what it would be on a waterfall scrubber. Turbulence is great for algae growth, and you get this from a waterfall scrubber.

[sporazoa]

I would also imagine that all depending on what type of algae takes hold, that for some it is more beneficial than others. Some algae are probably better at removing phosphates than others.

I also have an idea for a BETTER system of filtration that I encountered by accident already twice by coming in & out of the hobby. The last time I heard another reefer talk about it & the big AHA moment clicked at what was happening & why. I am going to write up a thread on this & you guys let me know what you think. I will like the thread once I am done posting it.

[sporazoa]

Here is the link to the thread I started. LMK what you think?

http://reefcentral.com/forums/showth...7#post24103677

[herring_fish]

Originally Posted by mattberrytr

I don't think it has been proven that waterfall scrubbers are so effective because the algae growth is pulling CO2 from the air. Personally I don't think this happens for any scrubber method - be it upflow, waterfall or even most surge scrubbers. The algae would have to be exposed to the air for a while before it's dry enough to absorb any CO2. It's much more likely, IMO, that the speed at which the water is flowing over the algae growth is allowing more nutrients to be absorbed by the algae.

When scrubbers operate submerged, they are usually in a sump, or an area of much lower flow. Even in a sump that has very high flow running through it, it's likely that the flow rate very close to the algae (which is what is important) is significantly slower than what it would be on a waterfall scrubber. Turbulence is great for algae growth, and you get this from a waterfall scrubber.

Originally Posted by herring_fish

I have to agree.
We are not talking about the underside of a tree leaf. Algae is adapted to absorb CO2 most efficiently via direct water to cell contact, not through air to cell contact. In nature, algal growth is strongest at the water line that stays submerged throughout the tidal cycle, not at the line that is out of the water part of the day or with intermittent splashing. This is also born out in the lab.

Regardless of the design, water flow, stable 3-D, static horizontal, UF or dump bucket, water to cell wall contact is more efficient than air to cell wall contact. This has been proven time and time again.
If you go to a planted fresh water forum, you will find that injecting CO2 can improve growth only if it is fully dissolved into the water column. Injecting bubbles or providing exposure to air is not as efficient as getting more water to the cell walls. Within certain limits, if you have more water flow, you have more water to cell wall contact so you get more growth.

[hkgar]

Originally Posted by Spar

I will be running my scrubber off of a manifold coming from one my return pumps. I currently have a 3/4" nipple coming off of it. I however made the 8" slot out of 1" PVC. Am I better off changing to a 1" nipple coming off of the manifold, or will attaching 3/4" tubing to 1" PVC be just fine as long as I am pushing through the required GPH?

It will just be a pain in the rear to get the new nipple put on, but can if necessary/better.

I also run mine off a manifold from my return pump. I would suggest that you install, in this order from the return, a ball valve and a gate valve. I adjust the flow with the gate valve and use the ball valve to shut flow off for cleaning. That way the GPH doesn't have to readjusted after cleaning. I use 3/4 inch pvc for the screen because Floyd has a piece that will fit over 3/4 to prevent the algae from growing up into the slot and interfering with flow.