Steel Container Tanks. I've sold these as commercial/industrial septic tanks as well. Superb condition. I have 23 for sale.
Measurements are 20 x 8 x 7.5, 9,000 gallons. I can do you a nice deal if you buy more than one.
Tanks have locking slots for safe transportation.
Tanks are $4000 obo each. Call/text Nick on 912 464 9507. Make me an offer!