Mega-powerful Nitrate And Phosphate Remover Replaces Skimmer, Refugium

[SantaMonica]

Today's build of the day is another one made from a gravel vac. These are easy because you don't need a special cutting tool to cut the slot in the pipe:

 

[SantaMonica]

I just finished up some diagrams of the most-used screen installations. The overflow-feed is good because it usually has a very large flow capacity, but, you can't turn off the return pump for too long or the screen will dry out. Also, pulsing the flow is not easy:

The pump-feed below will free you from the return pump, and makes it very easy to pulse the flow using a timer. But the pump must be able to deliver 35 gph per inch of width of the screen:

The sumpless-feed (or "bucket"), which was the original design, is how you get the screen up above the tank. The pump in this case goes in the tank itself. Also, the walls of the bucket let you flow more without worrying about water spraying sideways:

 

[andywg]

Hmm, that bucket design has me thinking. I could install a screen horizontally with the outlet from the sump return pumping across it and allow the two 4 foot bulbs to light the screen.

Either that or, as I have a spare pipe running back to the sump to control the flow to an associated tank on the same system I could install a screen attached to that, somewhat similar to the second diagram.

Decisions decisions...

 

[SantaMonica]

Reminder Of The Day:

Yellowing of the water: This is due to cleaning or scraping the screen while the screen is still in the tank water system (i.e., "in-system"). When you break algae strands, they release their chlorophyll related chemical contents, which drain downwards. If your screen is still in-system when you clean it, it drains into your tank system water, causing yellowing. Another cause of yellowing is not cleaning your screen at all. Solution: Clean your screen at least once a week, and do it by taking it to the sink and running tap water over while you clean it.

 

[SantaMonica]

Anybody here in the Los Angeles area have N and P problems, and want to test a bucket? My acrylic scrubber is getting ready to be functional by itself, so I'll be taking the bucket offline in a few days. This bucket has an original pre-grown screen from IA, and now is almost completely covered with real red/brown turf. It has four lights instead of two, and it also has a fan sitting on top. Comes with pump and timer too.

If you have high N and P, and you are willing to test N and P every day (I'll supply the Salifert kits if needed) and write it down in a log, then you can borrow it. Would be just a loan though. PM me if there is any interest.

 

[SantaMonica]

jski711 on the RS site says his scrubber fixed up his pH:

"my ph was dropping too low because i wasn't running my skimmer. the skimmer would help get rid of a lot of the co2 that was comming from the effluent of the reactor into the tank. so i turned my reactor off and i couldn't run my skimmer because of a medication i put in my tank, the skimmer would just overflow with bubbles in a matter of seconds. so i was running no skimmer and no reactor for about a month and a half. then after installing the scrubber i noticed that my ph was on the rise and has been high sometimes 8.5ish. so i figured the extra co2 from the reactor would bring the ph down and also help with micro growth. no more ph problems, im amazed at how much this scrubber has raised my ph. again awesome idea santamonica!!!"

 

[SantaMonica]

Here are some interesting technical points taken out of the current issues of Advanced Aquarist:

http/www.advancedaquarist.com/2008/8/aafeature3
http/www.advancedaquarist.com/2008/9/aafeature2


"Greater than 97% of the organic matter in the oceans is in the form of DOC"

"The majority of the DOC in the oceans is consumed over a time span on the order of hours-to-weeks."

"The generally accepted value of deep ocean TOC (DOC in this instance) ranges from 0.45 - 0.60 ppm, a number that appears to be insensitive to collection location. On reefs, however, the DOC (and TOC) value is considerably higher. Even with this point noted, the values of DOC on reefs from the South Pacific to Japan to the Caribbean to the Red Sea are remarkably consistent in their range: 0.7 - 1.6 ppm"

"Bacteria are a critical component in the food web of the reef, as they occupy the role of 'middle man' in the transfer of energy from the source (sunlight) to the consumers on the reef"

"sponges are some of the most prolific repositories of marine bacteria. In fact, some sponges have been studied as effective bioremediation agents in marine aquaculture as a consequence of their exceptional ability to absorb TOC"

"Where does the DOC go ... studies suggest that it is rapidly consumed by bacteria that live in and on the coral itself and not by bacteria present in the water column. Shutting down these endogenous bacteria by antibiotic treatment abolished DOC uptake."

"In total, these data unequivocally demonstrate that the [skimmer] is not required to deplete the aquarium water of TOC. Apparently, naturally biological processes are sufficient in and of themselves to return the post-feeding TOC levels to their pre-feeding values after about 4 hrs or so ... Clearly the skimmer is doing something, given the copious residue accumulated in the collection cup at the end of the week. Perhaps, however, the residue removed by the skimmer is only a rather small, even inconsequential, portion of the entire TOC load that develops in the aquarium water over the course of a week."

 

[eschaton]

Reading this thread, I've decided to give this method a try myself.

Even with skimming, a fuge full of chaeto, regular water changes, and what look like perfect readings, my tank has always been a bit algae ridden. I don't have any cyano, and aside from the clumps my tuxedo urchin carries around, precious little hair algae - I can even deal with the bubble algae. But I have dinoflagellates which form a carpet on lower-flow areas of the bottom of the tank every day.

The positive of trying this for me is when my fuge lights burned out last week (salt water got into the circuits). I had to install the new, glo T5-HO on the back wall of the inside of the tank rather than directly overhead (trying to drive screws into wood directly above my fuge in such a tight area proved impossible by hand, and I was terrified to try a power drill with so much salt water around). Though this light is further away and indirect, I felt like the higher output meant it evened out.

But having the light behind, rather than on top, of the fuge means it's ideally set up for this setup. I already built all of the parts using the gravel siphon method, although I used great stuff instead of silicone to cap of the end. I'm 99% sure this is reef safe (widely used for scaping in the poison dart frog hobby) and I had some onhand), and it cures fully within eight hours, although I think I'll wait a few days to install the system.

I wanted to ask though...has this model been "too successful" for some people? I'm already a bit concerned my snails and blue tuxedo urchin don't get quite enough to eat, and I don't want to starve them if algae vanishes from my main tank entirely. Maybe I'll just get some nerites to clean off the scrubber.

 

[SantaMonica]

Congrats on coming aboard! I'll trust your construction to be safe, since I'm not familiar with those materials. Too successful? Well the goal of the scrubber is to (eventually) rid the tank of algae. I keep 5 nerites myself, and I now have virtually no film algae, and just small spots of green that appear to be green coralline, I'm not sure. All the rest is purple and pink coralline. So you'll want to starting thinking more in line with non-algae eating occupants.

Opinion on your lighting: It will be a good test (and fun too!) to get it set up, and I sure hope it works. You'll know by one week; if there is a light brown growth, then it's OK. However, you might be underestimating the power of light required: If you double the distance of the light from the screen, you'd think that the power would be one-half. But it's actually one-fourth. On my acrylic unit the light are 1.5" away from the screen.

Anyway, let's give it a try and see what happens!

Reminder Of The Day:

What Scrubbers Consume: Algae scrubbers consume INORGANIC nitrate and phosphate. These things are what your test kits read, and what the nuisance algae on your rocks and glass require to live. What scrubbers don't consume is ORGANIC nitrate and phosphate. Organic nitrate and phosphate have another name: Food. Any and every piece of food you put into your tank has nitrate and phosphate in them, but they are organic. Scrubbers leave them in the water for the corals to eat. Skimmers do the opposite: Skimmers remove the organic nitrate and phosphate (food), and leave in the inorganic nitrate and phosphate; these inorganics are then used by the nuisance algae on your rocks and glass to grow.

 

[CFC]

This has been an interesting read, i don't do SW but big freshwater predators are my thing and they are living ammonia factories which in turn means high nitrates and large time consuming water changes to compensate. Andywg has suggested turf scrubbers to me before but the whole "tilting bucket" design seemed too complicated for me to be bothered to try, but i can easily incorperate a screen to run off the T'd off flow from my 2900gph pump that runs the sump on my 900g tank.

Give me a while to see what pipe and fittings i've got laying around and if i've got what i need i'll post up some pictures of what i've come up with.

 

[CFC]

Well that was simple and painless enough, one DIY turf scrubber built installed and running. I didn't have any screen since it seems that snails have decided the couple of pieces i had were tasty and ate it so I used a piece of 18x12" acrylic I had and rubbed it both sides with some coarse sand paper.

 

[SantaMonica]

Well CFC that's a swift and valiant attempt at battling the FW ammonia blues! Yes a scrubber can indeed fix your need for waterchanges, maybe permanently, since the only reason you are doing the waterchanges is to lower nitrates and ammonia (and these are the favorite food of scrubbers). And the setup you built in the pics will indeed grow some stuff on the acrylic sheet, and will be fun and instructive for you to watch for a few weeks (to prove that you could do it in under an hour, like you did!).

However, this particular setup that you built it is, unfortunately, not going to lower your ammonia or nitrate levels enough to make a noticeable difference in your waterchange schedule. So, if you like, I'll be glad to you show you what you do need to put together, but first why don't we have fun with some algae growth on the acrylic sheet for a while! You should see something by day 3!

 

[CFC]

I don't have any ammonia levels, the amount of biological media I have in the wet/dry and trickle filter areas of the sump takes care of that side of things very well. What I do have is high nitrate levels which although not an immediate problem to freshwater fish I would prefer to get them down to more reasonable levels, they usually run from 60 to 80ppm through the course of a week and with tapwater containing 30 to 40ppm even large water changes make very little difference to them, R/O water is out of the question since i would need a 200 gallon container just for storing water.

What I would like the scrubber to do is to lower the levels in the tank by 20-30ppm so that instead of changing 25% of the water (some 225 gallons) every week I can cut the changes down to just 10% per week which will take much less time and leave more spare time to work on my other tanks. I don't want to cut out water changes altogether as fresh water replenishes the buffers which keep the water stable, with the heavy polluting diet my large predators need pH drop happens very quickly without regular water changes.
Hopefully this swiftly put together attempt will take out some of the nitrate but I'm all for looking at a potentially better design provided it can be incorporated into my system without too much hassle.

 

[SantaMonica]

with the heavy polluting diet my large predators need pH drop happens very quickly

Well you'll be happy to hear that scrubber raise pH, and increase oxygen. Let the swifty job operate for a while so you can get a feel for it, and then I'll show you the setup that you really need. By the way, the big black tub in the pics... is that your sump?

Today's build-of-the-day is the very first solar powered screen that I've seen on any thread. Lighting will not be a problem with this one. Uses a simple pressurized pvc frame:

 

[CFC]

Yep the big plastic tub is the sump, it runs off a 900 USgallon (8x6x3') tank with a 3482 USgph pump so i needed something that was large enough to take the water volume but cheap enough to afford, a glass or acrylic sump of that size would have cost hundreds of ££s. The large blue canister to the left of the sump is filled with 30 gallons of alfagrog (ceramic media) which the water trickles up through from the bottom to the top via a central tube, the trays to the right are also filled with alfagrog (top tray has some floss for removing suspended solids) but are above the water line providing a wet/dry area for rapid removal of ammonia and nitrite after feeding. In a marine tank this type of filter would be a nitrate nightmare but for a heavily stocked freshwater tank it works brilliantly.

I really like the solar powered scrubber, i think it will be a bit cold to run one here at the moment but next summer i can see myself installing one of those outside the fishroom.