First - a picture so everyone knows witch bio load and photosynthetic load the aquarium is handling
Measurements I have done twice (shouting down the denitrification by stop dosing DOC) shows a rise in of the NO3 levels of around 5 mg/L NO3 a day. It is a part of my total nitrification rate but it is possible to do some calculations. 5 mg/L NO3 correspond to around 1.13 NO3-N. It means that 1.13 NH4-N has been converted to NO3-N. 1.13 NH4-N correspond to 1.45 mg/L NH4. My system is 300 L => 435 mg NH4 have been converted to NO3 during 24 hours.
My feeding contribute with around 154 mg N a day => 198 mg NH4 a day.
post 141 this thread
In the bottom of my reversed flow has an average of 0.34 mg/L higher than the DT. I have post 0.40 before but May was unnormal - I have take that away in these calculations. My flow is around 2000 L/day - it means that around 680 mg NH4 a day as most will come from the DSB.
Daily total input of NH4 into the system is 198+680 mg NH4 = 878 mg NH4. - Daily loss because of proven nitrification 435 mg NH4. Left to explain is 443 mg NH4 per day. I suspect that some will disappear by Anammox in the DSB but let us look at the worst scenario - all added and produced NH4 will be nitrified. With the best nitrification process - the Kaldnes moving bed with K5 carrier - around 400 mg NH4-N (514 mg NH4) will be removed daily and m2 area. 1 m2 area K5 is around 1 L carrier. Less than 1.5 L K5 in the right type of moving bed filter will nitrify my NH4 load completely. I do not use this technique - I use a fast flowing foam filter as nitrification filter.
Later on - in the fall - I will take away the nitrification filter and measure if my NH3/NH4 concentration in my DT rise.
Note that 878 mg NH4 in 300 liter correspond to an addition of around 3 mg/L NH4 a day.
Even if I am 100% wrong in my calculations I will get a nightmares of these figures - I hope that someone finds some faults in my calculations - it would be better for my nervs
I state before that I think that the nitrification rates are low in a normal aquarium. I still think that. If I look at possible area for nitrification in my aquaria - I will not stop at 10 m2. 1.5 m2 Kaldnes K5 manage this load.
This is very interesting and I will try to follow it up later in the fall
Sincerely Lasse