Constant Nitrate Problem

[fatman]

De nitrification is brought about by bacteria that are in an oxygen free environment. Typically that environment is supplied deep within live rock or in the bottom inch or so of sand in a deep sand bed (deep as in 5 to 6 inches). You are not providing either of those conditions meaning your only reduction method available is through water changes, and to lessen the increase in nitrates continue with a cleaning regimen.

[WannaRace]

I will continue with my weekly water changes on a regular basis. Last week I removed the rocks, placed them in fresh saltwater, and scrubbed them with a toothbrush. I then siphoned out any dead material off the sandbed and finally, did a water change.

Fatman, would you recommend me taking out my rocks every so often to scrub them of any dead materials? Or would it be best to leave them alone now?

[Bifferwine]

I'd leave them alone. Moving the rocks around and taking them out could be releasing all sorts of gunk into your water without you knowing it. The most I'd do to the rocks is blast them with a turkey baster before water changes to get any detritus off of them.

[WannaRace]

Sounds good, thanks Biff. I guess I'll leave it to time and water changes now. I added the smallest, healthiest looking damsel that I could find at the LFS. He is about the size of the tip of my pinky I plan to feed 3-4 times per week, while keeping the food to a minimum or at least until he stops eating it. Will test the water in a few days and hope to see nothing major..

BTW, I have been able to keep nitrates at a constant 20ppm week in and week out. These seem to be acceptable levels for some. I have read anywhere from 10-40ppm fish can tolerate. Obviously, 0 would be best.

[Bifferwine]

Fish can tolerate much higher than 40. They can tolerate in the 100s. Inverts are the ones that have a hard time with nitrates. That said, it's not good to let yours get above 20 just because fish can take it. Once they are high, it's extremely difficult to get them down again.

[WannaRace]

I just thought of something that, if it works, I'm going to kick myself for not thinking earlier...

When I do a water change on my 30 gallon, can I use the water I take out of there to do a water change on the 6 gallon? Would that be beneficial assuming all parameters are normal or would that harm the tank?

[Bifferwine]

The point of doing a water change is to bring new water in, to replace any essential elements used up, and to dilute out toxins. I don't think using water from one tank to do a water change for another would serve any sort of a purpose.

[WannaRace]

Ahh, I know what my brain was thinking now: jump starting a cycle. Nevermind then

[fatman]

When I used to keep a predator tank, or two, I use to use the water from my water change in my large coral tanks as water for the predator tanks. The water I was changing out though was fortified with Kalkwasser daily and there was a functioning mature deep sand bed and live rock, plus I did water changes weekly. The predators were such sloppy, dirty feeders and heavy poopers that the water from my coral tanks was like honey from heaven in comparison to their water. I really never worry about trace elements much with fish tanks, just the filth they create.