Works amazingly well.
Im using this co2 reactor on my 75g tank and very pleased with its performance. Installation was a breeze with easy to follow diagram. Fits perfect next to my oase canister filter even though from what my friends say this reactor is of impressive size. It does have some volume you to it and I love the clear housing because you can see everything happening. What I like most with this co2 reactor is it requires no internal media,no bypass and no electric pumps. Its design alone gets all the work done with a cool whirlpool motion inside. Even my friends envy my GLA co2 reactor. :)
Great product if you are tired of that fizzy soda look in your aquariums from inline diffusers or in tank diffusers. Much nicer than the DIY one I was using before. I bought one for my 120 and loved it so much that I got an another one for my 100 gallon.
My only complaint (and this really goes for all GLA products I have bought) is I feel like some documentation is really in order. It comes with an IKEA type drawing which is fine but it really could do with a manual. My advice when using this or other reactors is if you are using an inline heater as well don't use both a heater and reactor on one canister filter. Also this reactor will be very noisy while filling it is filling with water (and it fills up fairly slowly) but in my case by the next day it had filled and was quiet. Don't try to bypass this by filling up the reactor with water before you set it up. I thought I was being slick and tried this with my second one and my filter would not run properly. The reactor needs to be empty when you set it all up.