What are you doing to grow Hemianthus callitrichoides in a low tech tank? My tank is a 15g thats also low tech . I'm leery about using Co2 for two reasons, #1 I want my shrimp to breed, and #2, I've never used it before and I don't want to kill any fish or shrimp. I'm not new to the hobby, having started in late 1968 early '69 and in the 80's I gave it up for awhile. Now, 25 plus years later I'm getting back into it!
My tank finished cycling about 3 weeks or so ago. At the moment I have a single tube T-8 18" and 15 watts. In about a month I plan on going with a twin tube T5NO in a fixture 24" like the tank and a total of 28 watts. One tube will be 10000K and the 2nd tube 6700K.