[geefree]

http://cgi.ebay.co.uk/3-SPARE-FILTERS-WATER-FILTER-RO-REVERSE-OSMOSIS_W0QQitemZ350247968453QQcmdZViewItemQQptZUK_HGKitchen_SmallApp_RL?hash=item518c67dec5

mine last me more than six months making over 600 litres per day....

the rate at which the tank fill,s  slows down when they get dirty... but they still produce 00 tds....

but that is the time to change them, really.

[♠Winp®oClean♠]

Personally, I would go with twin DI's in your situation. My tap tds is 90ppm & I only use 2 bags of resin a year, at a total cost of £145 with a 500ltr van mount.

Less hassle, no waste, less problems in winter (freezing etc).

Even if you expand quickly & find yourself requiring 6/7/8oo ltrs a day, you can still use the DI's for polishing off, so they'll never go to waste anyway.

[♠Winp®oClean♠]

Another thing is, if you go down the RO on-board route, once your water has run out that's your day done so you may require a bigger tank/bigger van.
With DI's you can fill up from anywhere quickly, providing your working area has a similar mains TDS.

[Sapphire Window Cleaning]

My water is about 80 tds so would it be wise to get an ro with di as a backup?

It would be cheaper to get an RO system.
Most of us that have RO systems usually has a TDS reading after RO of around mid teens or lower.

If you had an RO set up, your membranes would last longer than most. due to the lower tap TDS reading.



Matt

[Sapphire Window Cleaning]

No I just plug it in at night, but you can have a split relay from your alternator.




Matt