Bio-Pellets are a form of Carbo dosing.
They can be beneficial, but just like Vinegar and Vodka dosing u can crash your tank (in a way) if not used properly.
I'm not an expert on Bio-Pellets, but I used it once with no success. I think I used too much... I always think of trying again though.
Some people get cyano out break when using it, a sign of to much nutrients in the water. But once enough nitrifying bacteria grows in the water column, it should start consuming nitrates and nutrients thus reducing them.
In a way, I believe u can think of the pellets as food for the extra bacteria in the water you will get from using (carbon dosing) it.
It's always recommended to use it with a good skimmer. The output of the reactor should be pretty much going right into the intake of the skimmer (or really close to it)
Higor
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