I have a friend who has a beautiful oak canopy with glass top on his 75g. He doses PPS Pro ferts every morning. He drilled a hole at the back corner of the canopy and ran a piece of clear 1/2" vinyl hose through the hole and into a space in the glass top's plastic back skirt just into the tank. He has a small plastic funnel stuck in the hose and just doses his ferts then pours the glut in. Looking at the front of the tank, you can't see it. Ingenious! OS.