Tank questions

[KF6OWC]

I picked up a couple of tanks today. one is O2 the other is acte. they are both out of Hydro. the Oxy is a 250 cf tank the Acte is ? (about 3 feet tall). can these be exchanged for filled bottles, both are about empty. the 100 dollars i gave covered the regulators and tips alone. so i dont feel like i have lost anything, but I would like to up grade the size of my current O/A tanks. any comments. would it be worth having them hydro tested to get them current? the Oxy tanks last test was 77! cant remember on the acte. tank.
anyway TNX jim :confused: