What water?

[dreamweaver]

Okay, so after the several years I've had a saltwater tank, I've never had to worry about this.... BUT, now I need to know what type of water I should buy to add fresh to my tank... Distilled? What???
What I've done to this point, is purchased water from my lfs... But in the last few months, we've been experiencing a "black slime like" substance all over our tank - live rock, glass, etc.... Several times we've removed everything, scraped the slime off the glass - scrubbed the rock, etc. Everything stays nice and clear until we add the water purchased from the lfs....
Soooo, I began noticing some of the tanks at the lfs - and sure enough, I spied the black slime... I also noticed the same stuff in the hose when they filled my containers....
To check things out, I've decided we need to try another water source - but unfortunately, we live in a very small town with only one lfs.... I know that I've read somewhere on this site about purchasing water from Wal Mart.... Not wanting to sound stupid (although I am) - exactly what type of water should be purchased? (I'm speaking of fresh water of course... For salt water I intend to use bottled live ocean salt water).....
Thank you for the information.

 

[lion_crazz]

Reverse osmosis water (RO) or reverse osmosis de-ionized water, if available (RO-DI) would be best to use.
Most Wal-Marts and even many grocery stores sell RO.

 

[tank a holic]

you can go to the big auction site and buy your own ro/di unit pretty cheap
i got a 100 gpd (gallon per day) unit but you can get smaller ones too
it'll save you lots of money and headaches in the long run
plus stores usually dont offer ro/DI water because you cant drink it

 

[spanko]

Walmart will have a water vending machine where you fill yourself their RO water. Check the maintenance dates on the tags to be sure they are changing filters regularly. Some have it for $0.39 per gallon. You can also use distilled water.

 

[small triggers]

and did you mention this to your LFS,, maybe they havent changed their filter and that could be the reason....just give them a heads up and wait till you see a difference before getting water there anymore.
And i agree with owning your own RO/DI unit if you have somewhere to put it... much cheaper in the long run...
Then you could purchase salt mix instead of sea water...