Excellent work. This should hold up a 30 gal
without any problems!
& William, 4x4 is WAY overkill for a 30 gal
stand. The compressive load rating (ie the load on a leg) for a 3 ft 4x4 (softwood) is over 15,000 lbs! <This is from my deck building book> As far as racking load is concerned (ie the sideway motion, or how wobbly the stand will be), as long as the entire frame is solid (you need to glue & screw the entire frame - or do fancy woodworking joints) 2x4's will hold as well. I wouldn't bother with 4x4 unless you have a 250 gal
or something monstrous!