What colour drop checker?

[Dolly Sprint 16v]

tank water is just as bad too

I know that now, but the instructions that come with the JBL drop checker tell you to use tank water.

Red Sea DC - Red Sea recommend using tank water + their solution, last year i ran with a Dennerle DC with their solution in the tank and a Red Sea DC with their solution + tank water along side one another to compare colouration - very slight difference in colour.

Paul.