Can't get a Gh reading...
My tap water seems to have zero Gh, Kh 27-28. I use 3/4 Ro/DI, 1/4 tap. I dose E.I. On weekly water water change, I add two tbs. Equilibrium (80 gallon tank, change half the water. API test Gh kit starts out pretty much colorless and stays that way, can't tell green from yellow. Bought a ELOS Gh kit. Supposed to start off red, then change to green. No red at start of test, light yellow to green as more drops are added.
AquaSoil now in the tank for 18 months, good plant growth, fish so-so after they get established.
What am I doing wrong on the Gh test?