I was browsing the pictures section and noticed the substrates in fenders tank and gayles tank. I thought they were fairly large gravel like mine. Fenders tank looks a lot like my 75 gallon. My question is have your tanks been running in that configuration for a long time? Do you use substrate heating? Is it neccesary? Do you vacuum or just perform water changes? I personally have not vacuumed in 6 months but I perform a 20 percent water change every 2 weeks or so. I've been monitoring my nitrates regularly and have found that they have not risen. In fact the nitrates fall to 0 and I must add nitrogen to the substrate regularly to keep the nitrate levels around 10. I've been using jobes plant food spikes for large indoor plants with a fertilizer profile of 14-3-7. I didn't come up with the idea, I saw it on another planted tank site. Its been working well for 1 month now. So far no algae and the plants are doing great. I am careful to monitor nitrates at least once a week until I get a feel of how much nitrate the plants consume.