Hey John! When we first started the hobby we use to use those. Lugged 12 jugs to the sore and took a good 45 min to fill them all LOL.. NEVER AGAIN!! We always tested the water before, never using anything higher then 10 iirc and never had any problems. Now though, I'd only use it if you were in a pinch or something.
Highly recommend getting a RO system and making your own water.