Thank you for the reply.
My phosphates are very low. My RO
does a great job with this. I learned the hard way that I need good water coming in.
I am confused about the role of GAC
. I thought this would removed dissolved molecules that give the water color. I never thought of it as a medium that could remove larger particles.
Also, it looks like most people don't do a filtration step other than a protein skimmer which apparently should remove most particles. I know that in my system the protein skimmer helps a lot, but it still seems that there are some particles aren't getting picked up.