My fish pond life started when I just put a dozen little feeder gold fish into a small tank at the bottom of a scenic water fall. They grew rapidly so I spent about 3K building a larger tank for my $6.00 worth of gold fish. Now they are the size of trout and once again I am looking at building a newer and much larger tank and waterfall. I am looking at using plastic stock tanks from Tractor Supply. I have also expermented with solar power for my pumps and I will install a larger system on the new tank and hopefully remove it from the grid completely. The entire experment has been fun. My wife loves our six dollar fish as much as me. Also, my current tank arrangement had a small water fall out of the larger tank and back into the original water fall basin. Last year, I found 6 new baby fish in the smaller tank and was waiting for them to grow large enough to move, but a desert toad got in the tank and had them for dinner. Bummer.Absolutely! If I were starting from scratch and had to buy the tanks new, a plastic tank would be the obvious choice. I would only consider a galvanized tank if I could buy it dirt cheap or get it free. I wasn't recommending them, just stating that they aren't completely off the table in all circumstances.
I just picked up an 8-foot diameter stock tank recently, on sale at a local farm supply place on an end-of-season clearance price that I couldn't pass up. Especially for the larger tanks, which take up a lot of space to store for the winter, now is a good time of year to find deals on stock tanks.