Sounds like a 30 gallon tank to me. As for the cost of a 30 gallon, I don't know. I got my 20 gallon at a yard sale for 15 bucks. I didn't even wanna go near a pet shop and price their tanks. The pet shop up town charged my friend 30 dollars for a 10 gallon. Come on, that's a bit over priced. Then again, the whole shop is over priced. 3 dollars for a feeder mouse? And he doesn't take care of his animals much either. Man, I cant wait till that place closes down.....

Oops....anyway...enough ranting, lol. That's all I can answer.