Along with the chaeto, we got dragon’s tongue to keep in the sump. The chaeto barely grew in the sump, but the dragon’s tongue did reasonably well. Dragon’s tongue is a beautiful macroalgae and looks very nice in a display tank, so we decided to move it into the main tank. The key however to dragon’s tongue is you either need to keep it spinning in a ball or you must anchor pieces to the rock. It does not work well to have it sit on the bottom of your tank and I will tell you why. First off, dragon’s tongue does not stay clumped as easily as other macroalgae so pieces may break free and mover around the tank. Second of all, if you have cyanobacteria, the cyano will grow right over the dragon’s tongue, as seen in this picture of our tank. Others have reported that dragon’s tongue can become a nuisance and take over a tank but I have not seen that first hand.