Carbon dosing balance

[The Saltman]

Hi guys,

I used to run zeovit and never had a problem with elevating phosphates. I switched over to v/s/v and prodibio biodigest and have always had 0 nitrates but phosphates are rising. They are up to 0.09 on hanna photometer. I talked with someone that said that the bacteria break down nitrate and phosphate in a balance. So if your tank doesn't have as much nitrate it will not break down all the phosphates. Zeovit seemed to be a good balanced system at this, but I'm trying to save costs by doing the v/s/v method. I keep trying to increase the ml per week with the v/s/v, but it doesnt seem to decrease the phosphates because I a told I'm nitrate limited. Any suggestions?

 

[Gomer]

It isn't carbon, but an easy solution to lower your phosphates is GFO. It isn't too expensive ime. I know you want to do v/s/v, but this is a way to bring things back to a level you want (short term fix)

 

[tmz]

I assume your nitrates are reading zero, correct? Are you feeding the tank ? Why would the phosphate be rising unless you are adding food?If you are nitrogen would also be replenished. An NO3 limitation would be hard to achieve since reef waters are very near zero but I suppose it's possible.
If after dou checking your tests and PO4 levels, you believe nitrogen limitation is the cause ,you can up feeding a bit or try some ammino acids to source N.
Alternatively a little gfo or even llanthanum chloride to remove or precipitate the excess phosphate can be used along side carbon dosing.

FYI ,the molecular ratio for carbon : nitrogen hosphorous, known as the Redfield ratio, is 106:16:1. This was established based on measures of phytoplankton content ; but . it is not a bad approximation for other orgainsms.

 

[The Saltman]

Yes, nitrates are reading 0. I feed every other day. Maybe I should try feeding everyday or using aminos?

 

[tmz]

Still doubt nirogen lim itation is the problem but you are in a better tposition to judge that than I am. Trouble with extra food is it equals extra phosphorous too.