test kits

Depends on the accuracy you want.

For the wealthy, LaMotte makes very accurate test kits (we're talking upwards of 50 USD for one test kit, and about 15 USD for the replacement reagents). Hach is also up there (quality and price wise), but is a little cheaper than LaMotte.

SeaChem, AP often get good reviews.
 
Aquarium Pharmaceuticals makes a very economical master test kit that has worked well for me. Their newer master test kit contains the 2 part ammonia test and the nitrate test which is especially great for beginners. You can also get the newer master test kit from Big Al's at a great price. ;)


master test kit
 
I use the Azoo Plant master kit and added either the kh or gh kit along with it. Dont recall which one as I am only on my 4th cup of coffee
 
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