Hello! Since I wanted to make a refugium for my 32 gallon goldie tank and I am kind of tight on budget, I thought about making them in clay. I want to grow some bog plants like lucky bamboo in it to reduce nitrate. I joined a local art club that allow me to use their clay unlimitedly. The idea is that the sump will sit in between the aquarium and the wall, and there are only 5 inches so it is kind of tight. The dimension will be 24"x19"x5". I will fill it with gravel and grow lucky bamboo out of it. Will that work? I am kind of concerned about the clay breaking under the pressure since there are no supports on the side. Again, this goes behind the tank so I don't care what it look like. How thick should the clay be? Should I glaze the inside of the sump? How thick should the clay be so it won't break?
Help is appreciated!