Switching to sand. Going with the tahitian moon black sand. Im running 2 FX5's do I have to worry about any problems with sand and my filters? Also how much sand will I need for 1.25"-1.5" my tank is 96"x24"??
I have 100lbs of Tahitian moon black sand in my 150g running an FX5 and XP3 without any problems. You will need about 140lbs (7 bags x 20lbs each).
A word of advice: Rinse the hell out of it! I rinsed mine one bag (20lbs) at a time, about 30 minutes of constant sifting per bag. Don't be afraid to rinse some of the sand out as well - the sand that goes flying around with little force from the hose. This will get rid of the less dense/lighter bits that could potentially end up in your filter later on if you don't rinse them out now. Then when you put it in your aquarium, sift through it again multiple times doing repeated water changes.