About two weeks ago I converted a deltec fr509 fluidized bed reactor into a sulphur denitrator. I bought a new top for the reactor that has a recirculation pump attached to it. The reactor is fed by my return pump. After about a week, the effluent read 0 nitrates( API, Hagen). A week later, the nitrates havent dropped at all (still 30) and have not gone down. All the people I have talked to have said it takes up to a month for the bacterial culture to really bring the nitrates down. I thought I would see some results in this weeks time but i haven't. Anybody have any ideas? Keep in mind, I feed 4 times daily(anthias) and the drip rate is about 1drip/sec. Also there is no escape for the nitrogen other than the effluent tubing.
sulphur denitrator
- Thread starter shankpa
- Start date
HighlandReefer
Team RC
The hobby grade test kits for nitrate are difficult to see changes, until the concentration has dropped considerably. It may take over a month before you see changes, especially in large systems.
ksouers
New member
shankpa,
You may find you have to increase the flow through the denitrator a little bit as it cycles. I haven't personally used one, but I followed closely a thread a year or so ago about several types of DIY denitrators. Never got around to making one as I eventually got my nitrates under control.
Anyway, regardless of design, they all started with a slow drip like you are doing and as the nitrates in the effluent dropped the drip rate had to be increased eventually reaching a steady stream. It also took some guys more than a month to cycle.
You might try upping the drip rate a bit to maybe 2 or 3 drops a second. Give it a few days to settle in then take a reading on the effluent. If it's still zero then up it a little more.
If you get a reading then hold till it drops to zero. It should be a minor reading, if it's a big one, say 10 or better, dial it back a bit.
You may find you have to increase the flow through the denitrator a little bit as it cycles. I haven't personally used one, but I followed closely a thread a year or so ago about several types of DIY denitrators. Never got around to making one as I eventually got my nitrates under control.
Anyway, regardless of design, they all started with a slow drip like you are doing and as the nitrates in the effluent dropped the drip rate had to be increased eventually reaching a steady stream. It also took some guys more than a month to cycle.
You might try upping the drip rate a bit to maybe 2 or 3 drops a second. Give it a few days to settle in then take a reading on the effluent. If it's still zero then up it a little more.
If you get a reading then hold till it drops to zero. It should be a minor reading, if it's a big one, say 10 or better, dial it back a bit.
