the od's are 8x4x2, water volume is 88"x40"x20" which works to 304 gallos. i got the top 2x6 cap on, 2x4 ring around the top and bracing blocks around the base in lastnight. i'll have pics up soon.
advice for those who want to save money by building there own tank, don't cut costs by buying wafer board!!! it sucks. it's not as strong, doesn'e even attempt to resist water, and is a #%@&% to seel. i estimate i may have been able to cut the amount of resin i used to seel down to a half or even a third of what i used. so really, it cost more in the long run.
here you can see how the walls are constructed. the second pic shows the bottom, which is also studded just like the sides so that i can insulate. i live in central oregon where the temp goes from 100 in the summer to at least one week of below 10 in the winter, and the tanks goin in the garage.