First I'll run down the nuts and bolts of my system.
90g/30g sump (system 6 months old)
100+ pounds LR
Good flow (two Koralia 4's, Mag 5 return pump)
Large recirc skimmer (Octopus)
refugium w/ rubble and chaeto (plenty of pods)
Not heavy on coral, but some SPS, LPS and soft corals
Livestock- 8 small to med fish, one RBTA, CUC
6x54w T5 lighting
RO/DI water, Seachem reef salt
10-15 gallon water changes every 1-2 weeks
Now, that's probably TMI, but I didn't want to leave anything out.
Ammo/trite/trate 0/0/0 (API)
Ca 360 (Seachem)
Mag 1050 (Salifert)
Alk 10 dKH (API)
phosphate undetectable (API)
High pH. Consistently 8.6, verified with one "pen" meter, one controller probe and test kit.
Slightly high alk.
Mag: I have, for three days, been slowly dosing Bulk Reef Supply Ca and Mag, the Ca is climbing slowly, just like I want. The Mag (according to the BRS calculator) should come up 50ppm per dose/day, but it has not changed AT ALL. Still 1050 just like when I started. FWIW, I am actually getting good SPS growth even with these numbers.
It seems that most people struggle with low pH and alk; I have the opposite problem.
I have not been able to get any info on how to address these problems... helpful people have pointed me to articles that would be great were I a chemistry major, but I can find nothing for non-MENSA members at all.
Any water gurus have any helpful hints on where the root cause may be? The pH is the largest concern to me.
Thanks in advance!