Discussing nitrate reduction

[Lasse]

Feed it with a slow going dosing pump in the ingoing water. Use a diluted DOC. Some dosing pumps can dose as low as 0.1 ml/min and these dosing can be spread during the day. I use 8 % ethanol (or vodka) and dose around 24 ml of this during the day. But I have a high flow system (high for nitrate destroyers) that give around 86 L/h. It gives around 2000 L per day through the filter. 24 ml/day 8% ethanol gives 0.012 ml per "run through" L of aquarium water and day. If you have 100 L/day through your filter - you need to dose around 1,2 ml 8% ethanol a day. If it is difficult for you to dose this small amount with an even distribution throughout the day - just dilute your DOC more. If you use a 0.8 % ethanol solution - you have 12 ml to distribute through the day. if it is 0.08 % - you need 120 ml a day and so on. You have to take all figures here between the index finger and the thumb - but at least you something to start with.

Sincerely Lasse

 

[WillpoleReefers]

Thanks for the info. Yes, my denitrator is basically the same thing. Not as big though. I have always run it off of a manifold for the feed water and then have a valve on the output to control the flow down to 1 drip per 2 seconds. So it’s fully controllable. My only dilemma is how to feed the carbon source into the reactor

Earlier in this thread I was questioning using my reactor without sulfur. That is basically what your deltec is doing unless that deltec media is made of something to support the bacteria, like sulfur. As Garriga said, I’d like to know what that’s made of.

I don’t think the Deltec medium has any nutrient function as the feeding is achieved using alcohol. What I have never been able to confirm is whether the Deltec fluid actually offers significant advantage over straight ethanol or even a home prepared alcohol mix. My plan was to get this running at the rate I want then trial switch away from Deltec fluid and monitor.

My nutrient is fed using a cheap Jebao type peri pump. You would just have to arrange a T into the pump line to manage this, via a small non return valve as on the Deltec.

Given that increasing flow by 3ml per min can switch this thing from denitration to aerobic nitrate production personally I would be wary of feeding it from a pump T arrangement. I think the inflow needs to be pretty precise based on initial experience.

Steve