any one know how to make.......

[bigmatt1992]

^^^^ a auto water top off system that i can stor under my tank. mind i have a 20 long for a sump so not much space to work with.

 

[Stray32]

The JBJ ATO is small and fairly inexpensive. I use it in my sump and it works great. You will need a reservoir of some sort to feed from. I use a 5 gallon modified "water cooler" jug, it fits perfectly right next to my sump under the stand.

 

[cloakerpoked]

http://www.bulkreefsupply.com/Auto-.../DIY-Top-it-Off-Kit-Premium/product_info.html

You'd have to add a top off pump (any powerhead or even an aqualifter dosing pump $14) would work for that. You could use anything as your reservoir.