I currently use a Merlin RO unit, but am looking to upgrade. The waste water on the Merlin is very high and in these times of high water costs it’s a cheap unit yet expensive to run. Is there a better and far more efficient alternative? I’ve looked at the RODI which looks good yet is a fairly expensive outlay and what sort of TDS could I expect from it? What other alternatives are there? 
check out the “pure Rinse” R/O anywhere system, The BEST bang for the buck!!!
I average about 99% removal of contaminants. Can any other system, say this? 
In other words, a 600 TDS source, and get 006 good water.
Give Shawn at RHG a call and he can help you out.
A 40" membrane system is prob your best option.
A standard 4040 will produce twice what a merlin does and has a waste ratio of 1:1 with decent water pressure.
WCR carries the full line of pure rinse systems… Everyone can check them out here:
http://shop.windowcleaner.com/category.sc?categoryId=174
Feel Free to ask Lance or myself if you have any questions about them.
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