Ok been trying to figure this out on my own but I can’t get my KH above 7 done several relatively large water changes daily for the last few days and still no change tried dosing seachem reef builder it just clumps as soon as it hits the water. Any help would be appreciated. Tank is 90 DT 40 gallon sump mostly zoas but I have a few lps. I am running a skimmer and a fuge.
Tank parameters are
Ph 8.2
Nitrites 0
Nitrates 20
Ammonia 0
Ca 420
Mg1400
Phosphates 0.01
Tank parameters are
Ph 8.2
Nitrites 0
Nitrates 20
Ammonia 0
Ca 420
Mg1400
Phosphates 0.01