DIY Nitrate filter?

[Kzonon]

I'm not a handy guy and my past DIY attempts have failed. (including 2 DIY attempts at overflows - no leaks, but didn't work and had fish casualties, I was not pleased with myself).

Anyways, I tried another DIY project on the weekend and everthing seems to be working so far, I was really excited and so I thought I'd post it but the results still remain to be seen. I know this is nothing new, and many of you have probably have done something like it before, so I'm open to additional comments, tips or hints. But the budget is primary here, I did not spend any amounts in the below:

I have a 125 gallon freshwater tank with an assortment of community fish, which overflows to a 25 gallon sump/refugium where I'm growing Java moss to combat my losing battle with nitrates. After, looking into various nitrate filters and the science behind removing nitrates, (Nitrates currently at 40 PPM) I took on the following DIY job....

So, what I did was I took an empty half litre yogurt container, filed it about half way with the filter media from used Brita drinking water Filter canisters. These were all spent media canisters as per the Brita instructions but I'm sure there's still life in them, and if not I figured it would pass for a substrate. Then, I filed the rest of the container with bio-balls. To keep it all in, I covered the opening with one of my wife's old stockings. On the lid, I punctured small holes around the rim and then in the centre another hole the size of an airline tube. Put the lid on and then pushed an airline down through the lid and the stocking, as far down into the media as I could. then, I connected the airline tube to a Tom's Aqualifter. Its what I use to prime my overflow. The aqualifter pumps at a reported 3.5 gallons per hour (the very slow flow rate needed to deal with nitrates, from what I understand.) From my kitchen sink test it appeared that the pump was able to pump the water to the bottom of the yogurt container and then up and out of the top. At 3.5 gph for a 150 gallon tank, it'll cycle the tank in just under two days but I guess, it'll take at least that to grow the anaerobic bacteria. So, the whole thing (except for the aqualifter) is currently submerged and running in my sump.

Its been about 4 days. The tank seems a little clearer but that could just be the added carbon in the system and not actually a drop in the nitrates. (The water is slightly cloudy green right now). I'll test nitrates again this weekend. I'll try not to let the results get to me and probably try to run this thing for a month to see if there is any change in nitrate levels.

thanks for reading.
Michael

 

[aquaculture]

hope it works cause this is something I could diy.

 

[Mr. Grumpy Gills]

something you could consider is a algea filter. there is a thread a while back about using algea on a vertical sheet to lower the nitrates.
http://www.monsterfishkeepers.com/forums/showthread.php?t=180385&highlight=algae+filter

 

[Nyquil Junkie]

40ppm is bad?
40 is about where all my tanks have been for years. When I had live plants they were a little lower in the one tank but not much.

I found that growing duckweed in the one tank lowered the nitrate below 40, and I could feed the surplus (and there is always a surplus) to the goldfish in the other tank.

I don't have any fancy or rare FW fish, just a mix of common tank fish. Corys, tetras, mollies, shrimp, snails, and a bunch of other kinds I pick up and toss in for color.

I don't often loose fish. I wasn't aware that 40ppm was a problem level for nitrates.

If it is, I might need to work on a DIY way of knocking that ppm down a bit myself.

 

[m1ste2tea]

40ppm is bad indeed. water nitrate levels above 20ppm is bad. and ideally should be close to zero. I am also currently battling with my nitrates with the use of plants and frequent water changes, I am considering this setup with an airstone driven pump for the slow flow rate

an airstone can be put into a pipe that is opened at the top, runs down to the bottom of the tank, turns around and follows up and over the tank into a a wide 4" pvc pipe, running all the way down to that pipe. gravel makes a decent medium, but I was thinking of using seachem de-nitrate media or something similar that can be recharged.

 

[Freezekougra]

since u have a sump you might want to try the algae filter as someone posted above
or you could fill it with house plants(submerge only the roots) like lucky bamboo or pothos

 

[Richies^Ghost]

I wasn't aware that 40ppm was a problem level for nitrates.

If it is, I might need to work on a DIY way of knocking that ppm down a bit myself.

It's not a problem, your fish will do just fine at this level, as you've found from experience. It can stunt their growth at higher levels and decrease their life expectancy, but generally it's not a huge concern.

That said, I'm doing my DIY best to remove all nitrates - the first step led me to believe a nitrate filter was the answer, such as in the original post. However the annoyance of making a filter with a slow flow, as well as the possibility of a power outage leading to some truly nasty being pumped into my tank when the power came back, led me to ditch this idea.

The second idea was an algae scrubber, as Grumpy mentioned. Being lazy and a tightwad however (hence why I didnt even consider chemical nitrate removal an option) led me to ditch this idea - paying for power to grow algae didn't seem like fun, especially when I had to throw it out every week. Why do people throw it out anyway - don't plecos eat it? You'd think they'd grow some fat ass plecos or something and sell them to pay for the power

So, now I'm trying out a deep sand bed in a bucket - basically its 10 inches of sand in a bucket, over which a steady stream of detritus free water flows. The first few inches of the sand are a regular bacterial filter, converting ammonia to nitrites to nitrates and consuming oxygen in the process. The lower levels are a different type of bacteria which convert nitrates to I don't know what, but the end result is 0 nitrates. I installed it today, so I will let you know how it goes

There's an 80 page thread over at reefcentral.com which discusses it - good read, though repetitive at times

 

[Richies^Ghost]

It's not a problem, your fish will do just fine at this level, as you've found from experience. It can stunt their growth at higher levels and decrease their life expectancy, but generally it's not a huge concern.

Depending on the type of fish that is - Discus wouldn't enjoy it I bet

 

[epond83]

I'm not sure this will work. All of the denitrators i've seen have a long tube, 1/4" or so coiled inside them about 50' to 70' long. The hose fills with regular bacteria, then inside the tube there is water with no oxygen and the anaerobic bacteria grow and convert nitrates to nitrites and on to nitrogen which out gasses when leaves the filter.

This is simular to the deep sand bed as mentioned, but a bit more effective (and more work)

I just made a coil denotrator about two weeks ago and it's cycling right now.

 

[Conner]

40ppm is bad indeed. water nitrate levels above 20ppm is bad. and ideally should be close to zero. I am also currently battling with my nitrates with the use of plants and frequent water changes, I am considering this setup with an airstone driven pump for the slow flow rate

40ppm is not "bad indeed". Ideally nitrates would be 0, but that is not possible for most fish keepers. I've heard of nitrates of over 100ppm in tanks where fish were flourishing and breeding for years and years.

While elevated nitrates can cause issues with fish, especially the more delicate ones, if you can keep your nitrates at 40ppm or below, you're doing a pretty good job.

** I'm not saying that you shouldn't strive for the lowest nitrates you can get, but saying they're "bad indeed" is spreading misinformation about the effect nitrates will actually have in the aquarium, imo.