Sulphur Denitrater Question

[jdhuyvetter]

I recently hooked up a Sulphur Denitrater (Korallin...the big one) on my system. System consists of 300 gallon SPS, 150 gallon softie, 100 gallon frag tank and a 150 gallon sump/refugium. The system has consistently had nitrates in the 20-25 ppm range for over a year. No issues with the corals. Everything was fine until I had a coral spawning event last month. Coral spawning in a closed environment is NOT A GOOD THING. Everybody was ticked off and I lost a bunch of frags and had some tissue recession/bleaching on the adult colonies. (Most have bounced back) As a result, I upgraded to the system mentioned above. Previous sump was 55 gallons with separate refugiums and frag tank plumbed in separately. Total system volume decreased by 10 gallons. After all that, the nitrates went back to the normal 20-25 range. Hooked up the Denitrater this weekend. At 1 drop per second, the effluent (at 2 days) was Nitrite, over 30 ppm, Nitrate, over 100 ppm, pH is 7.7 after passing through aragonite. System pH is about 8.0 to 8.1

Questions:
Anybody else have the same thing happen? i.e. Is this normal?

 

[chtan23]

I'm running the Aqua Medic Suphur denitrator and I have the same problem too, my nitrate from the effluent after 2 weeks is very high (~100ppm), my tank nitrate is ~20ppm. I'm using tropic marin nitrite/nitrate test kit. Might try another brand test kit to confirm.

How is you nitrate reading now?

 

[jdhuyvetter]

Took about a week, but settled down. Last I checked (about 2 weeks ago). Nitrates were 0 coming out of the denitrator and somewhere between 0 and 10 in the overall system. My test kit is not that sensitive.

 

[chtan23]

Thanks for sharing. I will test it again this weekend and see if the nitrate level drop.

 

[packer]

The nitrate reading will show extremely high due to the test being thrown off from the nitrite. When the units cycle and the nitrite drops to zero, you will get an accurate nitrate test. When it hits zero you can increase your drip rate.