I'm 5ft 6 and I can't reach the bottom of my 90!(LOL) I guess it would be kind of difficult to reach a tank at that depth unless you are a creature and have 12ft arms(LOL) I guess your best bet would be to make sure you have good flow to the bottom to keep any detritus falling suspended so you wouldn't have to make too much of an effort to vacuum every sq in. Also, I use a long siphoning tube. The suction part is about 1 1/2 feet long so I really don't have to stick my hand all the way to the bottom to clean. Now when it comes to aquascaping, I run into a bit of trouble. I hope your arms are longer than mine(LOL)