Nitrates won't go down

fishfanv

New member
My husband and I have a 40 gallon tank with LR that has been re-cycled after we let it go last year for awhile. It has been re-cycling since March. Finally in May all the params were spot on so we added some snails & crabs. At this point the nitrates were at 10 ppm. A couple weeks later we noticed the snails were dying off and the nitrates had gone up to 100 ppm. So we did a water change & brought the nitrates down to 50 ppm. Another water change after that and they went down to 25 ppm. So now the nitrates are stalled at 25 ppm and we cannot seem to get them below that. The only things in the tank are some leftover snails & crabs (3 total).

The skimmer is on 24/7. Does anyone have any suggestions for getting the nitrates down & keeping them down?

Thanks in advance.
 

fishfanv

New member
We're using a Salifert kit that is brand new, as our previous Saliferts had expired since we let the tank go last year.
<a href=showthread.php?s=&postid=15453781#post15453781 target=_blank>Originally posted</a> by dwd5813
what test kit are you using and how old is it?
 

GrimReefer82

Roll Tide!!!
Do you have a sump?

You can run chemi-pure and replace the media regularly. A nitrate reductor and/or a sump with a refugium and DSB will keep them down to 0.

There is something going on for the nitrates to be that high with no bioload.
 

fishfanv

New member
No, no sump, just a skimmer. We have a 30 gallon that is healthy & has been up for about 5 years. It has the same equipment as the 40 gallon, but is obviously doing better.
 

sedor

New member
What grimreefer said, use some chemi-pure to help clean nitrates. There has got to be something going on that is keeping your nitrates up so high. Could be your sand bed, you might need to change it out, especially if its deep. Could also be a change in the water your using. Its hard to tell there are so many factors. I would start by using the chemi-pure in a phosban reactor though, getting it all on the web should cost around $75.
 

buffalo123

New member
Nitrates reactors works; you can search them and easy to make.
I would try to find the source first and do some water changes, then check nitrates after a week or so.
You can also try chaeto in your sump it usually works
 

fishfanv

New member
so do you think changing out the sand bed would create a new cycle?

as far as nitrate reactors go, that sounds like a plan, esp. if they can be hand made.

i don't have a sump, so no chaeto for me =(
 

sedor

New member
Vodka would be helpful if they were willing to do the work.

As far as changing the sand bed goes you shouldn't cause a cycle. Like everything else do it a little slowly. Take out a quarter of it, wait a couple days, remove another quarter, etc. Then do the same while adding it. You could probably just wash your existing sand out real good and replace it. Keep in mind, this may not be the cause of your nitrates but if its an older tank with a deep or semi-deep sandbed, that's starting to look kinda grungy, it would be my first guess. Also, be prepared, you could stir up quite a mess, and don't forget to leave a little bit of the old stuff in to re-seed.
 

fishfanv

New member
well, the tank is old in a sense. it was established for a couple years but we let it go last year. then this year we decided to restablish it but haven't been able to keep the nitrates down enough. it's so frustrating because we can't figure out the cause of the nitrates so that we can get rid of them. if there's no livestock in the tank what could be causing the nitrates?!?!
 

Toddrtrex

Premium Member
What all do you have in the tank ? How much/often/what do you feed? Have you ever tested your make up water for nitrates? Before trying anything else, would see if you can find the root cause.
 

fishfanv

New member
the only things in the tank are: sand, live rock & 3 crabs/snails leftover from when we added the only time the nitrates have been down since we re-cycled.
 

Toddrtrex

Premium Member
<a href=showthread.php?s=&postid=15468900#post15468900 target=_blank>Originally posted</a> by fishfanv
the only things in the tank are: sand, live rock & 3 crabs/snails leftover from when we added the only time the nitrates have been down since we re-cycled.

Then I would think that there is nitrates in your make up water, or those rocks are really "dirty" and sloughing off a boat load of detritus.
 

fishfanv

New member
here's a run down of the whole tank:
tru-vu 40 gallon regular acrylic tank
live sand bed
about 60 pounds live rock
pc/mh lighting
skimmer
3 crabs/snails
we use r/o water
regular water changes
brand new salifert test kits

also, we have a 30 gallon that's been established since 2004 that is virtually the same but is healthy. it has the same kind of equipment, is fed the same food (when the 40 gallon had livestock) and receives the same care as far as water changes, etc.
 

seapug

Premium Member
Chemi-pure will not reduce nitrate. It may help keep it from rising more (if replaced often), but won't bring it down.

Sounds to me like it was just "let go" for too long. Since you have a skimmer you might try a vodka/carbon dosing routine. I've had good luck with AZ-NO3 and Brightwell BioFuel but there are many similar products on the market now that I think work much better than vodka.
 

GrimReefer82

Roll Tide!!!
<a href=showthread.php?s=&postid=15469221#post15469221 target=_blank>Originally posted</a> by seapug
Chemi-pure will not reduce nitrate. It may help keep it from rising more (if replaced often), but won't bring it down.

That is probably the most incorrect statement I have ever heard regarding nitrate removal. It will absolutely bring it down, I have seen it myself time and time again. For example a friend of mine had 160 ppm of nitrate in his 125 gallon and added some chemi-pure to his canister filter based on my recommendation and the nitrates went down to almost 0 in 48 hours! It was the ONLY change made to the tank.
 

fishfanv

New member
so we tested the water before we put it into the tank & there are no nitrates in it. so therefore they must be coming from somewhere in the tank :(

we bought some more live sand & will be adding it tonight. hopefully this will do something to lessen the nitrates.
 
Top