6-Pack, Size B, Rite-Size Cartridge Refills

Great price works great

Performs the exact function described. Works very well.

could not use wrong size to small

Works perfectly.

Great

This is the easiest to use, most complete, and easiest to use kit on Earth. It has guided me thru my new Aquarium and I am so satisfied! This fron a 50 year okd aquarium aficionado. Thank you!

Good

My fish are happy so I am Happy! Thank you

Exactly what I expected. Cheaper than our local pet store

very good.