...well how about the same re-circulating water at 86F and 7.5pH. These are custom tanks 25 x20 x 16", so they are pretty deep. I wanted to experiment with a multi-layer type of zebra environment, stacking them both high & wide. I find these guys as high as 12" above ground, enjoying the top capes/slates. The three top tanks are plecos and the lower tanks are discus tanks. Notice how the water level is lower in the Zebra tanks....just need to add some powerheads for more current..., so far, everybody is happy with twice a day water changes!!