I am using a 55 gal fish tank going into 2 10 gallon grow beds. I was thinking of adding two more but was not sure if it would be to much. I still need to find a grow media most likely going with lava rock or river rock anyone have any opinions on this hydro-ton is not in the budget yet. That is half of why I am waiting to add the next two grow beds. I will attach some photos let me know what you guys think its still a work in progress. But I am ready to start cycling my water as soon as I find a grow media.