potassium test

[N-dog]

is there a test kit out there that doesn't cost $50+

[HighlandReefer]

According to posts here, the accuracy of the hobby grade potassium test kits leave a lot to be desired and may be off significantly. The only way I would trust one is if you used a couple of known standards which are in the testing range you are looking for to make sure it is correct. This could get complicated and more expensive. :)

[Randy Holmes-Farley]

I do not know the costs of any of them, and I'm not convinced that they are accurate, but tatu recommends the Fauna marine over the KZ test here:

http://www.reefcentral.com/forums/showpost.php?p=15746287&postcount=57