Hey all

I talked with the principal at the high school where I teach, and it looks like I will be taking over the Aquatic Science program.

I want to update the set-up, so I am looking for some advice from anyone who would like to help

Here's the plan

27 20gal tanks ( 24 display for students and 3 refugium)
1 50 gallon sump
a large (4' tall) double beckett skimmer (I am going to build it)

all of these will be connected via the sump drilling the tanks and putting
overflow drains (PVC) and then 4 pumps to as returns and to run the skimmer.

Question I may need help with

1. What size PVC should I use as drains into the sump?
2. What size pumps should I use? (3 return pumps - 9 tanks each and 1 skimmer pump)-BTW, these need to be submersable pumps
3. What diameter of acrylic tube should I use on the skimmer (the one I built for my home system is only 24" tall)?

I have lots of DIY experience, but I have never set up a system this large, and I just want to make sure I do it right.

thanks for the help

ace