Nitrates won't come down no matter what we do!!

[Ace25]

I have always found nitrates the easiest "problem" to fix. Since there is really no ill effect with lowering nitrates quickly a nitrate problem can be fixed in under a week if you have the time and $ to do it. I have fixed tanks with nitrates over 200 in under 5 days, getting them down to under 10. The way I do this is LARGE water changes.. talking 95%. I did this on a 100G tank and it took 400G of water ($100 worth of salt, 2x 200G boxes of Reef Crystals) to fix it. It went from a tank neglected for over a year to almost pristine looking in 5 days time by doing almost complete water changes daily. First day, nitrates start at 200, do a large water change, nitrates are down to 100 immediately after water change but 24 hours later it is back up to 160 due to nitrates leaching from the sand and rocks. Just keep repeating the water changes until the nitrates finally stay down, at which point you will know they have pretty much all leached out of the rocks and sand. After the 4th 100G water change on the tank, 24 hours later, nitrates finally stayed under 10 and now that the owner keeps up on maintaining the tank it has never risen above 20.

[SantaMonica]

Problem is obvious... lighting not in front of the screen, and wrong screen material, is only giving you 1/4 of the filtering.

Throw that material away, and find a way to get the lights one light reflector directly in front of each side of the screen. You'll probably need to get side-reflectors.

[Jasonandmolly]

OK, we'll try replacing the screen material. We already have the canvas - we bought it a few weeks ago in case we decided to try that. For the lights, I see what you mean - but considering there are still 6 lights on the thing it shouldn't be not working at all.

[kerry]

I had doubts until I got my screen and lights right, now its zero nutrients across the board!!!!!

[Jasonandmolly]

@Ace25 - thanks for explaining... we've tried water changes with no change in nitrates at all, but not huge changes over and over like that. We'd wondered if nitrates were leaching from rocks and sand to the point that we can't get them to go down below 40-80. My husband wants to take all the stuff out of the tank and trash it and start over, he's so annoyed. It's been like two years we've struggled with either hair algae or nitrates and thankfully the algae is gone. But he feels like he's just not good at keeping a tank, for whatever reason, even though he tries hard, researches, and isn't any less smart than anyone else who would set up a tank! LOL It'd be hard to get up the water supply in our house for that big of a water change, but we'll keep that idea in mind.

To everyone: Is it likely that our nitrates will spike for awhile now that we're putting a new (seeded) screen in and took off the old screen?

Thanks!
Molly

[Floyd R Turbo]

They might. But it depends on many factors. If you have a lot of LR (2+ lb/gal) and it's well established (and porous) it will do a pretty good job of keeping N down for a couple of days, and the slime that grows on a new screen is actually quite efficient at N export.