I've been interested in using an ATS for quite a while. Probably since back when David Grigor posted all of the information he gathered after using an ATS for years. I just never got around to building or buying one. I picked up a Turbo Aquatics ATS a couple months ago and finally got it installed this afternoon. When I had initially set up my 90g I had a primary return and a secondary return that ran through a UV sterilizer. As well as a herbie drain setup. Since my secondary return pump failed a while ago and I haven't been running the UV, I decided to modify the drain system into something of a cross between a Herbie and a bean animal drain. So I pulled the check valve and lok-line to leave a bare standpipe, trimmed and moved around the vinyl tubing to connect it directly to the ATS from the second standpipe. Reduced the flow through the primary standpipe to get enough water flow. Other than needing to tighten the seal on the bulkhead that came loose in the process of converting the return to a drain, everything went about as smoothly as I could have hoped. Now it is just a matter of letting it grow some algae for a while before doing my first harvest.