i use domestic rainwater drain guard plastic mesh instead of a diffuser sheet to block the clowns aggression. the same stuff can be used for everything, and its cheap as for a roll. it can be cut to the rough shape of the reef to hold her in a section. if u have a
DSB plastic poles attached at each end of the net can hold it indefinately.
my tomato was drawing blood everytime i put my hand in, to the point that i wanted to see if she could fly, thankfully i chose my first option.