Nitrates wont go down!!!!

[cmonti]

20 gallon tank about 5 months old.. Ive been running purigen in my aquaclear filter, crushed live rock and I have a nitrate reducer in my filer media canister in the skimmer. 10-20% water changes every 7 to 10 days. Nitrates wont go below 40. I have a few beginner corals and this morning noticed a few closed up. Checked nitrates and they look closer to almost 60!! What the heck is going on. Thanks

 

[jackri]

What kind of water are you using to do water changes with? I'm also confused as to why there would be a media canister in a skimmer? Sounds like a filter not a skimmer. What do you have for a bioload and what do you feed?

 

[spanko]

is the crushed live rock in the aquaclear filter? If so get it out, it is trapping detritus and your nitrates will rise as a result. Use the purigen and some filter floss in the aquaclear and change the filter floss often to remove the trapped particles in it. At this point a 50% water change, after doing the above, will reduce your nitrates by approx. 50%

 

[clown-lover]

Have you tested your water recently with your LFS? My nitrates wouldn't go down either, with purigen and chemipure. Turns out my test was bad. LFS guy said that the nitrate test in my kit is known to go bad. Just might want to double check it with someone. Good luck

 

[maddhatter]

Is there rock in the tank? If so, where did you get it? How long was it cured? It could have been half dead and not curing can cause a large surface area of dying organisms. Causing the high nitrates.... Just a thought

 

[jstdv8]

how much are you feeding? how many fish do you have?

 

[srfisher17]

I don't think either Purigen or Chemi-Pure will do much, if anything to reduce nitrate. They are great products, but reducing nitrate really isn't what they are for. IME & IMO; most artificial products called "nitrate reducers" don't work. What product are you using?
I really like Aqua-Clear filters and have used them for different jobs for about 30 years. I had one that ran non-stop, except for a move, for 25 years. Their foam blocks are big, not little pads combined with cheap carbon. They are very easy to rinse every day or so--they hold an incredible amount of crud. But, in some set-ups the foam block actually become a main culture spot for aerobic bacteria and rinsing one can cause a problem in small tanks.
I agree with Henry, a box filter usually isn't a good place for crushed LR; but what else do you have for reducing nitrate? Any LR? If you need a little help short-term; you can keep the media bag of crushed LR on top of the foam in the AquaClear. That is back-asswards, but will keep most crud away from the crushed LR. Keeping nitrate low in a small tank can be tough. A small bio-load, aggressive water changing, and enough LR is the only way I know to do it. BTW, is this a reef or fish-only tank? Fish can handle nitrate at 60ppm with no problem (IMO&IME). Inverts are another story.

 

[cmonti]

I have 20 lbs of live rock. Two clowns and a small yellow tang I plan to move to a bigger tank as he grows. Assorted mushrooms, trumpet coral, kenya tree, flourescent star polyp. I feed a small amount of pellet twice a day and mysis every few days. I also feed the tang seaweed on a clip. I dont have a reverse osmosis system so I use distilled water. I have a Red Sea prism skimmer, which I know isnt the best in the world, but does pull some nasty stuff out of the tank. The deluxe model has a media basket inside where I have the nitrate reducer. I have seen the spike in nitrates after I replaced the biomax with crushed live rock in the aquaclear. I was told by my LFS that this would ceate more of a natural filtration process. Everything in the tank seems to be ok besides the star poly (closed up). Should I get the rock out of the filter? Why was I told to do this???

 

[spanko]

Yes you should get the rock out of the filter IMO. You were told to do this because people thing that adding rock will increase biofiltration no matter where you add it. In the small container that is the Aquaclear "filter" you are just trapping detritus, the bacteria on the rock is breaking it down to ammonia, then nitrites and leaving the nitrates with little or no way to convert them. Over time this will just be an increasing problem as you have now way to clean the detritus from the rock.

 

[cmonti]

thanks for all the advice. Ive taken out the LR in the filter and replaced with chemical media. Not ive got the foam pad on bottom, chem and purigen on top. From anyone's expereince, does it matter where the purigen is placed on the filter? Is it ok to be on top?

 

[srfisher17]

Chemi-Pure and Purigen do pretty much the same thing and using both is a waste of $. They should be on top of the foam in an Aqua-Clear and you need to clean the foam often and thoroughly. AC filter blocks hold a lot of hidden crud that you don't want hanging around.
Just adding to what Henry said: LR rubble, or any media used to remove nitrate, will not work in high flow conditions; and that is the case when LR rubble is used in a power filter. The bacteria that reduce ammonia/nitrite to nitrate thrive with high oxygen ; but the bacteria that remove nitrate are just the opposite.

 

[florida joe]

nitrate testing needs to be spot on or you will get a false nitrate reading, just food for thought

 

[srfisher17]

Yeah, and nitrate test kits are notoriously unreliable.

 

[btldreef]

Why not get your tests double checked at the LFS?
I recently bought a new phosphate test kit and I guess it had sat on the shelf too long because it read terribly off from what the actual reading should have been.

 

[srfisher17]

This sometimes works. But, the LFS results are often just as bad. Several years ago, a few of us fish geeks had water tested at several major LFS from New Orleans to Pensacola. Then a friend, fellow hobbiests, and marine chemist ran the same water samples thru their lab. Only ammonia was always within 20%. Nitrate wasn't within 20ppm at any of the stores. Phos, alkilinity, silicate, and a few others were way off as well. This may have been the geekiest experience in my life, but was interesting.
Just a side note; if corals and other inverts are showing no signs of a problem and nitrate is reading 60+ppm continuously; I wouldn't trust the results. If you do have an accurate test kit, test the water at your lfs, 10 to 1 says its 80+ppm. I hate to admit it; but while nitrates in my little 55 reef are always <20ppm; my big FOWLR tanks are never under 60-80 ppm.

 

[beaslbob]

nitrates come overwhelming from the bioload and are measurable only because your nitrates consumers have not kept up with the nitrate producers. Water changes will not bring down nitrates to unmeasureable levels at normal water change schedules (like 10%/week or so).
To bring down nitrates you need to add or expand the consumers. I recommend macro algaes (in a refugium is best) because they also bring down phosphates, consume carbon dioxide and return oxygen and fish food.
my .02

 

[beaslbob]

oh yea be leary of nitrates test kits. some are calibrated for "total" nitrates other calibrated for the nitrogen only part of nitrates. The conversion facter is over 4 nitrate-nitrogens for each total nitrates. So one test will read 1/4 the assuming both are accurate and the test water the same.
my .02