The problem is not the center brace melting. Acrylic is a great at retaining heat. If the center brace gets too hot and water splashing on the brace it can crack. Sort of like a hot glass and cold water. If the brace cracks you can have a failure of your tank. If you have an acrylic tank you want to keep the center brace cool. You can use fans in your canopy to circulate air. If it should become too hot, let it cool slowly, dont try and drop the temp fast.