Yeah but wouldn’t the food breakdown introduce phosphate?Oooo - something else caught my eye here if adding more meaty food doesn't have an effect - take your floss offline.
A floss will take out the larger uneaten food particles and the larger dissolved solids/wastes, but will not pull out the amino acids or the phytos (too small). So relatively speaking it's only letting the "High N low P" stuff pass thru and pull out the "High P" stuff.