salt

So my current LFS is being a bit unreliable with my salinity and i've been interested in mixing my own salt for a while now. i currently have a 20g nano reef with a 10g sump, but i'm going to be upgrading soon to a 120ish gallon reef. I'd like to know what a good RODI unit is that won't break...

I just noticed My salinity is around 1.018 and i don't own a RODI unit yet so I have no way of raising it since it's Christmas Eve and I have no idea if any stores will be open tomorrow, I have about 3 gallons of RO water in a jug so I might be able to mix salt water should I get my hands on...

I am looking to buy a 10 gallon saltwater tank for Christmas. It will have filters, heater, pumps, live rock, a couple fish, a coral or two, and a deep sand bed. Water changes will be done every week. Because it is so small do I really need to spend all the extra money and buy a protein skimmer...

There was an excellent thread put together quite some time ago now by Billybeau1 and hilgert. I've referred to it may times to see if someone is close to the expected values of a particular saltmix. There can of course be slight variations and if any settling has occurred in the mix before use...