Cammywammy
Aquarium Advice FINatic
- Joined
- Nov 22, 2012
- Messages
- 513
ok. That could be the issue. If you have an unusually high or low KH, it would throw off the accuracy of the drop checker to the point of making it unusable. I would suggest trying some 4dKH reference solution. Using tank water is not the best method.
something like this: 4 DKH Reference Solution for CO2 Drop Checker Ph | eBay
Or you can make it yourself using distilled water and baking soda, if you have some good measuring equipment (graduated cylinder, gram scale to .01).