@david. If you are going to go through the process of buying a pump and doing all that. I would recommend you get a GHL Doser. It can handle your ATO, and have the trojan purpose of having a doser for alk and Ca. I know they are a little pricy, but I like there easy of use and power user functions. Plus I don't trust, Apex to run my reef. I don't want want a catastrophic failure like some of the horror stories that are circulating the internet. I feel the GHL product line is high quality works on wifi internal access and internet access from iPhone app if you do dynamic dns and port forwarding. a GHL doser 2.1 is my go to system right now it has be 3 months so far and know on wood. I have not run into any game breakers.