testing

i used something a tester for my fish tank a while ago ,because all my fish died in a week,that may be suitable for my experiment . it basically tested the water. one of the issues i found with using this as an indicator was that is was difficult to read the key. other than that, it was pretty understandable. i found the tester at BIG W, but i thought i could check out some local pet stores and find anything that may be better