Distilled vs. RO/DI water

[JKurtz]

What are people's opinions about using distilled water for topoff and water changes instead of RO/DI?
I've got a friend who stocks up on gallons once a month (when they're on sale for about 69 cents at Kmart). Prior to that, he was just using tap water. Now he claims his corals have never looked better. Ideas?

Jeff

 

[erasmu]

I would be very careful about what type of coil elements or materials are used in the distiller. I have heard that copper tubing is routinely used. That might leave a small amount of copper residue in the water. "Safe to drink" for 200 lb humans is different than fish that are fractions of an ounce or delicate corals. There may be very good distilled sources available out there, but be cautious.

 

[JKurtz]

That's a good point. Of course, there's probably nothing on the label to indicate whether copper coils were used or not. I think I'll take the "better safe than sorry" approach on this one. And perhaps I'd better advise my friend to do the same.
By the way, can anyone suggest a reasonable RO unit that's affordable on a writer's wages (i.e., one step away from the poorhouse)? What's the minimum amount I should expect to spend? Which source is recommended?

Jeff