well i built the sump out of 1/4" glass. i had to custom build it becaues of the odd shape of my stand. the sump holds just under 20 gallons.
and as for the three jugs. thats my 2 part dosing liquids cal, alk
and mag. if you look closely to the pictures you will see my dosing pump right behind my reef-angel controller. i probably wont need to dose for a while but when i built my last stand for my other tank i didnt have room for my dosing pump so i havent been using it. since im gonna turning the other tank in to my aggressive/ non-reef safe fish with very little corals in it so i dont need to dose.my bi-weekly pwc
keeps all my parameters in check...