Constant Nitrate Problem

W

WannaRace

Reefing newb
Before anyone tells me that this project is just simply not going to work, I would like to exhaust all options and paths to success.

With that said, I started a 6 gallon fish-only tank a little more than a month ago. In the display I have 6 lbs. live rock, sand, powerhead, and a HOB filter that has two compartments which water flows through. In the first compartment, I have live rock rubble only. Then the water flows to the second chamber which houses some denitrifying rocks (basically very porous rocks that absorb ammonia, nitrite, and nitrate). Finally, it flows back into the tank.

The problem is, I have never seen nitrates drop below 20. I do a 17% water change once a week. Before I change the water I test for nitrates and see that during a weeks time they jump to 40-60. All other parameters are spot on, perfect.

Any ideas as to why this dramatic increase occurs? I realize that in such a small tank huge changes easily happen, however, why isn't going from, let's say, 0 to 20 in a weeks time rather than 20 to 40 or 60. Any suggestions?
 
Keeping nitrates at zero in a 6 gallon tank is a daunting task.There just isn't enough water volume to work with.Maybe increase water change to double the amount and reduce feeding-bioload.
 
I am using distilled for water changes, but tap with a liquid dechlorinator for top-off. I tested the tap water for nitrates and saw 0ppm. Anyway, I am switching to RO for top offs to see if that helps any. I wonder if, although ammonia and nitrites are at 0, the tank is still cycling...

I will try doubling the amount in water changes, however, I have added no livestock to the tank. Until I see stable water parameters I do not plan on adding anything. I can play with my 30 gallon while I wait :)
 
Today I am looking to siphon out all of the brown, what looks to be die-off from the rocks. Is it advisable to take the rocks out and shake them in saltwater to remove everything? It would make siphoning out everything off the sandbed a lot easier. Then I plan on doing a water change, leaving the top open, and testing for nitrates again.
 
Try using a powerhead and blowing that stuff off the rock.Then siphon it out.Thats a lot easier than scrubbing each rock in a bucket.
 
No problem taking the rocks out and giving a good rinsing in fresh saltwater.I would go as far as scrubbing the dead stuff off with a old toothbrush.I believe the cycle is over but the decaying matter is raising the nitrates.If you're going to use tapwater,Prime is a better dechlorinator,it detoxify ammonia,nitrite and nitrates on top of heavy metal and chlorine.
 
I agree with both Yote and Freak, you can either blow off the crap with a powerhead or turkey baster and catch it in a net, or you can scrub the rocks one by one with a toothbrush.
 
just let it wait a bit for the cycle to really come to a rest before you get too discouraged. i would use a brush and get all the stuff off the rocks in a seperate container just so it lessens the chances of more crap staying in there. you may not be able to suck it all out if you kick it up all over the tank
 
Thanks guys..I really think that the nitrates were never getting lower than 20 because I was only changing the water, when in fact, there was a LOT of die off and other crap within the rocks and on the sandbed. I blew it off with a turkey baster, siphoned most of what I could from the sandbed, and while I still had debris floating around I did a huge water change. I guess I will continue to do this until I can reach some stable water parameters.
 
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.
 
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?
 
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.
 
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.
 
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.
 
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?
 
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.
 
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.
 

Similar threads

F
New to marine.
Replies
2
Views
1K
kbuser92
kbuser92
J
Help with Nitrates!
Replies
0
Views
1K
Jeff P.
J
Mike
We're Back!
Replies
0
Views
700
Mike
Mike
R
Clowfish
Replies
0
Views
876
Reef aquarium time
R
J
Help With Dying Fish!
Replies
0
Views
1K
Jeff P.
J
Back
Top