I am thinking of buying some co2 equipment off of Craigslist. The guy Is offering 2 regulators 1 is a ma957 not sure the other but is a Milwaukee brand. Also comes with a SMS122 ph controller and 20# co2 tank. Is this a good deal or no? I also have to drive about 2 hours to go get it. I am planning on using it on my 75 gallon aquarium.
The 20lb cylinder is the most valuable item of the bunch.
If it were me, I'd buy the package, sell the two regs for $100, keep the pH controller just to play with (it'll need a new probe), and have just spent a grand total of $50 for a big cylinder and a new toy
If you don't have any experience with CO2, a used Milwaukee isn't a bad way to start out. But you only need one, so you can make some of your money back.