No, I’m not adding any more tanks. However, the new stand I just built will only accommodate two 20g long tanks. I have three up and running. The just finished stand holds one tank (at the moment), and I have a store bought metal stand currently holding the other two.
The metal stand works great but it’s too low, specifically the shelf for the bottom tank, which is just inches off the ground. It’s impossible to gravity drain that tank. I do use a python hose, but not to regularly vacuum/drain my tanks. See this post on what I normally use to clean/drain my tanks. I don’t like wasting water, which is what the Python does when running the faucet to create suction. For tanks that are higher than my utility sink, I will sometimes use the Python just as a drain. If you don’t have good water pressure, the Python doesn’t work as well as a substrate vacuum. It doesn’t work at all if you’re relying just on gravity, and the tank you’re draining is lower than the drain end of the Python hose.