Ok Im ready to build a DIY R/O system...

Anyone have any good build blueprints for a do it yourself reverse osmosis water setup. I would like to keep it in my garage and do all my salt mixing and water changes without hauling my containers to my LFS...Sure could use some ideas here.

 

By the time you buy a good membrane, you may as well have bought the system prebuilt....

EDIT: Well, maybe you meant to fill a garbage can or similar. If so, you can throw a RO(DI) unit next to it, have it always connected, and run an ATO unit so it'll fill the container with RO water; then you just have to mix in salt, with your powerhead and heater in there, and pump it out to the tank (if you go big).

 

agreed.. its much cheaper to buy one.. DIY you wont save money.. its just one of those things..

 

+1 with bama....I dont think I've ever seen anyone DIY a RO/DI unit just because they come prebuilt for less money and trouble than its worth I think!

 

Have you done a cost-savings analysis yet? I'm not sure that DIY'ing anything will save you a whole lot of money. You're more than welcome to try but there's really not much to it I don't think.

This place sells the whole units as well as the individual components that you could probably use for a baseline comparison. There are some other online stores that might even have better prices.
Reverse Osmosis & Deionization - English

 

I built a five stage 100gpd with seperate components for $75 bucks with "economy" cartridges. It didn't last 2 months before the inline meter was picking up TDS. I ended up buying a 100gpd unit from a vendor specializing in this area for $125 + free shipping. I now wish I'd just gone that route to begin with because for the $200 I actually spent I could have had a uber nice RO/DI.

 

One thing to note is that as long as you have good quality filters and a good quality RO membrane and you have it setup properly with the proper pressure and flow rates etc, the construction really shouldn't matter that much except for how easy it is to do maintenance etc.

 

The thing is, nearly every part on an RODI unit is going to be the same exact plastic pieces everyone has; it's the membrane and other media's quality that's different between units. There's no real room for variance between housings to use for the RO membrane, the fittings, or the other chambers.

 

I disagree. There are thousands of types of plastics out there, and many of them are used to make cartridge housings. There have to standard formed areas of the housing in order to hold the cartridges, but there is still plenty of room for modification in design including threads, O-rings, wall thickness, etc. I would argue that some plastics may be suitable for drinking water in an R/O application and be utterly useless in reef applications because of silica and VOC leeching.

Fittings are another area of concern. For drinking water and many other applications brass fittings would be just fine, but in a reef brass might lead to copper in the water, especially if applies post DI stage.

I agree with the overall sentiment of the thread that the OP should consider a commercially available unit over DIY for this. Well made units are available for almost the cost of components and usually come with warranties and are pre-tested doe leaks. Many suppliers even use their systems as a loss leader to sell replacement cartridges, which means you'll not be able to make a comparable system for less money period.

-Doug

 

There can be a big difference in the quality of components, especially the housings and 1/4" fittings. Many ebay quality systems use housings from China which are very brittle and crack easily. Look for the ANSI/NSF and UPC approvals on the housings, tha tmeans they have gone through rigorous testing to ensure they are not only food grade plastics but can withstand normal working and surge pressures too.

There is no way you could build a quality RO/DI for what you can buy one for. The vendors get big price breaks by buying in quantity.
I would use the CSP-DI found here for $145 complete as an example.
SpectraPure Customer Appreciation SALE! 20% - 50% off

You would need to buy 3 canisters, a RO membrane housing, a top bracket, a RO membrane, a quality prefilter, a quality carbon block, a refillable DI cartridge, 20 oz of fresh DI resin, a dual inline TDS meter, an inline pressure gauge, a flow restrictor, numerous 1/4" John Guest fittings, stainless steel screws and some 1/4" tubing in various colors to build it yourself.
Some of the low end ebay units are less money but do not include things like the TDS meter and pressure gauge plus the quality is questionable too so you have to weigh the advantages and disadvantages.