Hello icupkn 3,

I have never seen CO2 tablets that were designed to be dissolved in a resivior.
Maybe you can pass on more info, like the name of the product.

I do use in my personal grow a product made by Supernatural, called Excello CO2 emmision pucks. These are designed to be dissolved in a small amount of water, in a seperate container, and they do raise the CO2 level. My flower room is 6'x6'x6' and 1/2 puck will raise the level to well of 1000ppm at peak and averages 800-900ppm over a 6 hr period.

The down side is they are not the cheapest way to obtain CO2 enrichment. Or maxium level with good control.

OM