Let's assume we have relativelly high level of phosphates in
the 58 gallon tank. There are three ways to deal with the problem:
- partial water exchange with let's say 12 gallons water with no phosphates
- usage of phosphate removal media like PhosBan, Phosar etc...
- partial water change AND phosphate removal filters.

Intuition would tell me that the third option will be most effective.
But what to do first? Should I put phosphate removal medium and
extract as much phosphate as phosban is able to and then change water?
Or maybe do water change first, and then lowered phosphate levels
treat with the phosban? Or maybe it does not really matter?