Sulphur Denitrifier

[Leko]

Hi all,

Q) SD effluent says 20ppm nitrate - in tank nitrate 0 ppm. How? why?

My SD was cooking along just fine. I set it up according to "Parker" from his video. Worked fine and as he said.

I didn't pay attention to the effluent rate since it was working - mistake. It's all jacked up now and the effluent reads 20ppm now matter the drip rate.


However, in-tank nitrate is 0 ppm. How? What's going on?

 

[Lasse]

Hi all,

Q) SD effluent says 20ppm nitrate - in tank nitrate 0 ppm. How? why?

My SD was cooking along just fine. I set it up according to "Parker" from his video. Worked fine and as he said.

I didn't pay attention to the effluent rate since it was working - mistake. It's all jacked up now and the effluent reads 20ppm now matter the drip rate.


However, in-tank nitrate is 0 ppm. How? What's going on?

What do you measure your nitrate with? Its sounds like you had run into the classic trap that nitrite affect the nitrate readings. Sulphur Denitrifiers are know to sometimes (normally in the start phase) generate nitrite. Nitrite in the water can give false nitrate readings because most nitrate measurements kit first convert nitrate into nitrite - after that the kit analyse the nitrite level and the colour chart convert back the colour into nitrate. In some test the "false" reading can be up to 100 times the nitrie concentration. As an example your nitrite concentration is 0.2 mg/L NO2 - you nitrate reading kit report 20 mg/L nitrate with some of the test kits.

Sincerely Lasse

 

[Dr. Reef Verified Sponsor]

If you are using the same testing method to check the tank vs the water coming out of the SD and still there is a 20ppm difference. Then you need to reduce the rate of drip out of the SD to let bacteria convert the nitrates. For now reduce the drip rate for next week or 2. Once water coming out of SD has 0 Nitrates then start increasing drip rate slowly everyday till you start seeing incdrease again. That day you slow it down to previous days drip rate and that would be your sweet spot.

 

[Leko]

Thanks guys, great help. You were right.

Nitrite 1.0 ppm from SD effl.

Dr.Tim talked about this in a video. He said , if the bacteria has gone anoxic (too slow flow or clogged filter) your nitrite will rise. I have "restarted" the SD filter by opening up flow (too fast).

Thankfully the in-tank nitrite is 0ppm.


thanks again

 

[Leko]

Still confused...

Ran the filter too fast - Nitrite dropped to 0-.25ppm - Slowed effl. flow back down - nitrite went back up to 1ppm.Should I slow down effl even more?

It's currently running at 40ml/min. for a moderately stocked 125g.

What should I do? Take the filter apart - clean media - restart? I think this is what Dr. Tim said in his denitrification video, where he covered SD and other methods.

The display tank is looking and running great. All the dinos are almost gone and no algae problems. In- tank nitrate 0-5ppm Nitrite 0ppm.

I'm hesitant to mess with something that's working. I went through dino-hell and now I'm on the other side.