Help with nitrates on new setup

[jumplittlechloe]

Tank is 120g with 30g sump. Tank has been up for 1 month. Tank was started with dry rock and live sand. After the cycle I did 30% water change.

Currently:
0 ammonia
0 nitrite
100 nitrate
? phosphate (untested)

I am having trouble getting nitrates to come down. I did add an continuum exxodus nitryx brick this week in hopes to build my anaerobic bacteria to address nitrates. I have continued 20% water changes. I have considered starting carbon dosing but I am not sure. Thoughts/questions?

 

[N4sty T4te]

It's probably the dry rock, that stuff comes loaded with dead stuff. The fastest way to bring it down would be to dose a carbon source and skim it out. Something like Red Seas NO3: PO4 X would work as well.

If you didn't cure the dry rock your nitrates will probably continue to rise for another 4-6 weeks and has been known to leech phosphates for 6 months Plus. So don't dose anything too drastically thinking it's not working because that 100 PPM will probably continue to rise.

 

[pdt7361]

Your dry rock would be what I'd question too. Where did you get it and what if anything did you do with it before adding it to the tank?

 

[N4sty T4te]

Also if you do any water changes I'd recommend doing an extremely large one of 90-100 % after the nitrates stop moving up.

You definitely want to look into your phosphates though and report back those numbers...

 

[jumplittlechloe]

Will check phosphates. Dry rock was from another reefers tank. Think it was acid washed and dried. I will start carbon dosing unless someone has a reason that would be unwise at this time. Currently have diatoms and see some faint green spots on the rock.

 

[N4sty T4te]

I don't see why it would have any real negative effect. I'd prob still wait until the nitrates stop rising before starting to dose. That way you'll at least be establishing what its doing without guess work. How did you start the cycle?

 

[N4sty T4te]

Once you pull rock out of a tank and dry it it has t0 re-cycle from the die off :/

If it came from a run down system with very high nitrates in it the the rock would absorb it and then leech it into the water column as well. It's that way with phosphates anyways, I'd assume the same for nitrates.

 

[jumplittlechloe]

I started the cycle with Dr. Tims bacteria and his ammonia. I am testing the nitrate on a salifert test. The nitrate test has held at 100 now for 2 weeks, however it could be higher as this as high as the test reads.

 

[N4sty T4te]

You might double check all of the numbers on the ammonia dose too, sometimes if you accidentally over do straight ammonia you get crazy nitrate numbers as well... was the live sand from another tank as well, or was it purchased new?
-B

 

[jumplittlechloe]

I dosed as his directions stated on site, but your statement about ammonia/nitrate correlation is what I suspect. The sand was purchased new CaribSea Aragonite Special Grade Reef Sand.

 

[N4sty T4te]

Definitely could be. All I can tell you is that I cooked my dry rock for 3 weeks, gave it an acid bath, scrubbed it, pressure washed it, etc. and it still gave me 10 PPM nitrates by the time it was all said and done.

 

[jumplittlechloe]

Check with the reefer I got the rock from he power washed the rock and gave it a muriatic acid bath.

 

[N4sty T4te]

Was it taken back to dry before you added it to the system? If so it's sort of the same deal in that everything alive on it dies off and it has to be cured again...

 

[jumplittlechloe]

Yes it was. It was dry prob. for 1 year or more (guy had it stored in tubs).