Sulfur denitrater won't cycle

[reefslugs]

Sulfur denitrater won't cycle. I bought Midwest Aquatics sulfur reactor. I have had it up and running now for five weeks. The nitrates coming out of the reactor are at 50ppm. My tanks nitrates are at 30ppm. In the instructions it says to start out at one drip per second for three days. After that bump it up to two-three drops per second. Some people have said not to bump up the drip rate till the nitrates are at zero. Which this is what I have done. Five weeks of running and the nitrates are higher then the tank. I'm frustrated. What should I do?

 

[Randy Holmes-Farley]

Which kit?

Some kits (like Salifert) will read a little nitrite as a lot of nitrate.

 

[reefslugs]

Which kit?

Some kits (like Salifert) will read a little nitrite as a lot of nitrate.

I'm confused. I'm surposed to be checking nitrates out of the reactor, right? I've tried Salifert and Tetra. Which I get different readings from the two. If I test my tank water Tetra says 100ppm, Salifert says about 30ppm. I don't know which one to beleave. I already went through the hole Salifert KH be incorrect.

 

[Randy Holmes-Farley]

Yes, I'm just warning you that the Salifert nitrate kit will read excessively high if there is nitrite, and nitrite may be in the effluent of a denitrator that you are setting up. You'd need a nitrite kit to check that.

Nitrate kits are notoriously inaccurate anyway.

 

[Nanook]

Your denitrator can have nitrite or nitrate in the effluent. I would use a Lamotte nitrate kit for low-range testing. As for nitrite, I use Salifert. I think it just takes a bit of time as well, nothing to be too alarmed about.

 

[reefslugs]

OK I've got a Tetra nitrite test kit. So I just tested the water out of the reactor and to my surprise, it's off the chart. Tested the tank and it's zereo, thank god. Whats up with this? Somethings not right. I'm adding 100% nitrite in to my tank. I'm getting ready to throw the thing in the trash. What could be the problem? The sulfur is surpost to be seeded with bacteria. Should I try adding bacteria like TLC or Special blend to the reactor? Or should I throw the sulfur away and by new? Please help me!!!

 

[RBU1]

If your reading a higher nitrate reading from the effluent versus the tank you need to increase your drip rate. Does the water coming out of the reactor have a sulfur smell?

 

[Nanook]

It is just the age-old cycle Ammonia>>>nitrite>>>nitrate....soon the nitrate will disappear...give it time.

 

[Nanook]

If your reading a higher nitrate reading from the effluent versus the tank you need to increase your drip rate. Does the water coming out of the reactor have a sulfur smell?

NEVER increase the effluent rate if you are reading nitrate or nitrite.

 

[reefslugs]

If your reading a higher nitrate reading from the effluent versus the tank you need to increase your drip rate. Does the water coming out of the reactor have a sulfur smell?

I thought if the effluent is higher in nitrates, slow the reactor down. No I don't smell sulfur, and I read if I did to bump up the drip.

 

[RBU1]

When I was running a sulfur denitrator if the unit was putting out a higher nitrate reading then my tank it meant the unit was producing nitrates. So you slightly increase the drip rate. I had several sulfur denitrators.....

To be safe call the manufacturer tomorrow and ask them....

 

[RBU1]

NEVER increase the effluent rate if you are reading nitrate or nitrite.

Not true.....Sulfur denitrators require proper flow thru them and it takes some time to get it right. If you are reading a higher nitrate reading out of the effluent then the tank you need to increase the drip rate. What is happening is the unit is making nitrates to help feed the bacteria in the unit. I have been thru the aggrevation of getting one of these right several times. When you get it right they are great......

 

[Nanook]

Well, we will agree to disagree then I started my SULPHUR nitrate reactor with nitrates close to 30 on a 1200 gallon system and over a period of several months am down to nitrates of 4.4. Everything I have read, and I can give you links, states that if you are reading nitrates or nitrites out of your reactor that you should NOT increase flow. You might decrease flow, but not increase. These have been used successfully in Western Europe for many years and I have read everything I could get my eyes on and or translate

Here is a link with some pretty easy to understand directions:

http://www.aquacare.de/download/anleit/b-adn4.pdf

 

[reefslugs]

This is Schpitters instructions, which is the same as Midwest Aquatic.

Leave the valve open and let the water flow through the unit for 24 hours. This will allow any trapped gasses to escape. Close the valve and only allow one drop per second to escape. The unit should be run for 3 days at one drop per second. Then the drip rate can be increased to 2 - 3 drops per second.
(Monitor your system closely when increasing the drip rate. If your system is poorly aerated additional oxygen may be needed.)
Once the filter is mature and the nitrate level in you aquarium is undetectable the drip rate may need to be increased. If you smell sulfur from the unit the drip rate needs to be increased. With adjustment the long term drip rate will be determined. This will be system specific since every system is unique.

 

[reefslugs]

Oh boy. Here is the instructions from the DIY forum.


How did you adjust it?

One drop per second during first 3 days. Then ramp it up to to 2-4 drops per second and let it catch up. After that every tank is different, but here are some guidelines:

If you smell sulfate (end product) your bacteria is not gettting enough food (nitrates). Ramp up the flow or remove and store half the media for later usage.

I kept my reactor at one drip per second this interior time. I'm thinking my reactor matured, and now is rotting from too slow of flow.

I'm thinking I should drain all the water out of the reactor and start over. Doing what the instruction say to do.

 

[Nanook]

Hmmm, I am scratching my head on this one! Does your effluent smell like rotten eggs? If so, increase the flow rate and see what that does. Main thing is to be methodical with any change you make and test your tank nitrate and reactor nitrate/nitrite to see what is happening. I posted on my thread in SLASH Forum what my progress was to give an example. I am seriously debating cutting back on the flow rate now so I don't drop to zero nitrates all of a sudden.

 

[RBU1]

Trust me.....Slowly increase the drip rate......

 

[Randy Holmes-Farley]

If you smell sulfate (end product) your bacteria is not getting enough food (nitrates). Ramp up the flow or remove and store half the media for later usage.


Whoever wrote the DIY directions does not have a good handle on chemistry. You cannot ever smell sulfate. You smell hydrogen sulfide. The difference may seem trivial, but it is the same difference as between ammonia, nitrite and nitrate. One needs to understand the chemistry to make informed suggestions.


If you are reading a higher nitrate reading out of the effluent then the tank you need to increase the drip rate.

In this particular case, the Salifert kit is likely giving false high nitrate readings, based on the nitrite test result. So one needs to be very careful how one proceeds since the denitrator is not necessarily generating any nitrate.


I'm by no means an expert on denitrator tuning, but it seems to me that if the nitrate is only getting partially reduced to nitrite, rather than all the way to N2, that one wants to increase the residence time in the denitrator by reducing flow, not by increasing it. That said, if it is just a matter of waiting for additional bacteria to build up, then just waiting longer may be a fine plan.

 

[vegaskid11]

When I set my SD up I set the drip rate to about 1 drip per 2 seconds and had it drip into a bucket. I only tested nitrite for the first few days and it reached 0 at about the third or fourth day. After the effluent reached 0 for the nitrite I then put the effluent drip back into the sump. The next day, I tested nitrate and it read 10-25 ppm (salifert) out of the unit. The 5th day the effluent read 0-5 ppm nitrate and at that point I bumped up the flow about 10%. After bumping up the flow the no3 would increase to about 10ppm. I continued testing no3 everyday and when the effluent would reach 5ppm I would increaes again. I continued increasing flow and testing until I reached a flow of 4x the amount of sulfur I was using. In my case I used 3 liters of sulphur so I am currently running the reactor at a flow rate of approximately 12 liters per hour or 200 ml per minute.

 

[JMBoehling]

I started mine about 5 days ago. The effluent Nitrates went Sky High around day 4 and now they are dropping back down, I imagine they will be at 0 by tomorrow.. I have mine setup in tandem phosban reactors. The LSM is in the first and I have ARM (Aragonite) in the second one. I think the second reactor went through a quick 4 to 5 day cycle and that is what is giving the high Nitrate readings (As they are much higher than my current reef tank readings) My drip rate is 1 drip per second via a aqualifter pump.

Jim