NEED HELP STAT!

Water change %15
Cal 440
Kh 9 (no dosing since additional, test hour after NaCl/H20 change)
Nit 0

Ancient test kits, going to order new.
Just did:
Nitrate < 2.0
PH 8.1
SG 1.025

Missing instructions for Cal and KH kits, going to find em' online and download.

Nitrate is probably correct.. 90gal Tank, 30gal Sump. Small bio load Only 6 smallish fish.

2xDamsel (lol, i know but I like em')
1xChromi (lives in overflow see Damsel above)
1x Tomato Clown
2x Yellow Tangs (still small)