I am no carpenter but here is my opinion. Firstly, that does not sound like a lot of tanks to me (unless I miss counted). Just keep in mind that water weighs about 8 lbs / gal. I usually figure 100 lbs/ 10 gallon tank. If your really worried ask around for advise locally. I have kept many more gallons of water in an upstairs apartment (given it was a newer structure....but I bet thats a con...old homes were built to last, not to be disposable like newer buildings are today). ------------------------------------------------------------------------- This is the apistogramma mailing list, apisto@listbox.com. For instructions on how to subscribe or unsubscribe or get help, email apisto-request@listbox.com. Search http://altavista.digital.com for "Apistogramma Mailing List Archives"!