Review on Optimize CO2 Monitoring: JARDLI Glass Drop Checker for Planted Aquarium Tanks by Mandy Nelson

I have several different lamps to control CO2 waste. This works fine. Several people have mentioned in their reviews that it is difficult to pour the liquid from the bottle to refresh or clean the liquid. The easy fix is to just use a dripper or dripper to get rid of the old liquid. Like I said, it worked great for me and the size doesn't seem out of place for my 20 gallon tank. Four stars because I haven't owned it long enough to give it five. The time will show.