can't afford ro/di what alternatives
 

if you can't get a ro/di system can you just fill up those 5 gal jugs at the machines that cost about $.25 a gal or buy distilled water. I live on San Diego and we have thee worst tap water. I am going to initially fill my tank with filtered sea water but as in water changes what do you suggest?

I'm in SD as well and only use water machine water for topoffs. The TDS of the Glacier machines I use averages 30 from my experience and has been fine for me for 4 years.

That would be fine, but almost certainly more expensive then a home RO/DI unit in the long run, especially for a 55+ system.

I agree that distilled water is likely okay, and expensive over the long run. It might be a good way to get started, though.

I used those machines for years. Look at the inspection stickers for a date and check it weekly. Find out when they are serviced, I would show up when the guy was changing filters and he would "test" the system by filling up a few of my containers for me. It's good to get to know the guy ;)

Rather than using a machine, go to one of the stores that has a live person on staff like Water & Ice. They always have a conductivity or TDS meter handy and are happy to test the water for you. The problem with unmanned machines is there are no health codes requiring any sort of maintenance or standards that have to be met. Some of the manned stores sell ice cream and have soda dispensers so they are subject to health codes of sorts. The water may not have to be xx TDS but at least you know there is some sort of sanitation being practiced. I have found the Water & Ice by me to have great quality water every time I take my TDS meter with me. Our tap water TDS exceeds 800 and their RO only is always in the 13-17 TDS range which is remarkable considering the quantity of water them make in a days time.

Go to a water store like culligan or whatever you have mine has a TDS meter I can check with a push of a button and gives me any reading and even how pure the water is so i know the quality at all times.
They usually have deals for long time purchases I get 500 gal for $50.

I got to walmart. The machine is .33 cents a gal and a TDS reading of 10PPM and you can also buy it buy the jug it's distilled water if you do that and the TDS is usually around 5PPM. I was going to petco .08 cents a gal there and the guy kept telling me how they just changed out their filters so the water was great, and I believed him. Couldn't figure out were all my algae was coming from till I got my TDS meter and found out petco's water was almost as bad as my tap.LOL Hav'nt had any probs with walmart though.

Save your money and buy a ro/di system, even if it's a cheaper one. It's worth it for not only the convenience factor but also because you know the condition of the filters. I wouldn't risk your setup on some retail store dispenser.