We had been using Aquarium Pharmaceuticals liquid tests. We found that the colors were hard to compare to the kits, and the dangerous chemicals were a concern with kids in the household.
We just recently got the "Mardel Master Test Kit 50 Tests" test strips. We like these a lot. They are easier to read, very comprehensive, quick, and safe.
They have a wider range then the liquid tests we had, and included a water hardness test which I had been having trouble finding at the store. I can test for everything in 2 minutes, and dont have to worry about storing them.
Regards,
Artuk