design suggestions.

[BCreefmaker]

well i have decided to put back up my first nano design, with really only some size modifications to fis the inital bugs, its going to be pretty much the same demesions, just have a higher backsplash for where the overflow runs into the sump, a slightly longer overflow peice, so the water dosent run and drip all across the bottom of the main tank into the sump, add enough room for a Euro Reef RS-80 in sump skimmer and a more chambered and organized sump. its going to be 25 display gallons in the top 18" cube, and a 14 gallon sump. my last tank was lacking on flow so this im i thinking of getting a 600gph pump and adding 2 rotating water deflectors for wave effects. first of all i just want to know will i have to make a larger sump? with that skimmer and my pump wont the turnover in the sump be terrible? im going to make it so the water dosent have to go through the sump fuge as fast all the other chambers. secondly will 3/8" accryiclic be thick enough for 25gallons or LR and sand and water? my last tank broke under the strain but it was only 1/8" with 8 gallons, or should i go with 1/2" just to be safe?
heres the old picture with the new dimnesions, cuz im lazy and you can use ur imagination :p
http://reefcentral.com/gallery/data/500/127600tank1.JPG
A)1- 18"wx25'h
B)1- 18"wx18"l
C)2- 28"wx25"h
D)1- 18"wx28"l
E)1- 18"wx9"h<-sump height adustement
F)1- 18"wx19"h<-overflow/ tankheight height adjustment

any comments or suggestions are once again welcome and very appreciated.