I really appreciate your feedback!
I purchased the GLA diffuser - The difference wasn't enough to buy the cheaper one and deal with issues. Plus GLA has been great support.
I wanted to know how it can be so small and still diffuse CO2 when compared to the DIY reactors that seem to be so large.
They explained - It has an atomizer inside which causes the CO2 to diffuse into small bubbles - it then shoots them into the tank, and some people don't like that. The DIY reactors just shoot CO2 directly into the reactor and it tumbles around - which is why the reactor needs to be so large. It doesn't shoot bubbles into the tank, but the trade off is that it uses more CO2.
I want to try it out as I'm also plumbing the heater inline and space can be an issue under the tank.