ro/di waste water!

I am new to here and I am looking to start a new reef tank.I have had 30 gallon and up to 150 gallon tanks but not one of them saltwater.I now that you need to use distilled water or ro/di water but I have a hard time with putting 4 to 5 gallons of water down the drain just for 1 or 2 gallons of ro/di water.Can you store the waste water and run it back in to the system aging?

 

Well, since the RO/DI system has an input from a tap, you aren't really able to run the waste water back through the unit. Unless you take a small pump, put it in the waste water, and attach the pump to the ro/di unit with the right attachment. I wouldn't recommend re-using that water, though; it was filtered out for a reason. All the bad chemicals & etc were filtered and went to the waste water, so I doubt you'd get much usable water out of that stuff anyway.

 

I use a BRS water saver 150GPD, which sends the waste from one membrane over to the inlet of the second. I have been very happy with it for the 15 months I have been using it. Spectrapure makes a few systems that use a 2:1 waste to water ratio (they also have some 1:1, but they are very very pricey). But no, I would not recommend running the waste back through. The water comes out at a much lower pressure than it enters, so hydraulically it would not work unless you pumped it back in AFAIK.

 

OK!! So is there a system that does not produce as much waste water as some of the others out there?

 

See my post above.

 

+1 to all the above.

Running the wastewater back through would also expend your filters more rapidly as it has a higher TDS concentration.

FWIW, the wastewater isn't necessarily a waste; it can be stored and used for laundry, watering flowers/gardens/house plants, or anything else where the TDS count is irrelevant. It's just not suitable for your SW aquarium.

 

Absolutely!

Let the water run down the drain where it will eventually find it's way into the ocean. From there it will evaporate and form storm clouds that will add water to your local aquifer. The water utility will draw the water from this aquifer where it will be available for processing through your RODI filter!

 

I have my waste water going to my flowers beds.

 

Yu would have to boost the waste or brine back to 60 or whatever psi to run it back through. The waste serves a purpose, it carries the TDS the membrane away so it stays clean and functions well. When you mess with cutting the waste ratio you risk fouling the membrane prematurely and costing yourself money. Those who advertise a dual membrane system as a water saver are doing you an injustice unless they tell you upfront you are shortening the membrane life and increasing your cost of ownership. Dual membranes increase GPD but the waste ratio should stay at 4:1 since you are sending concentrated brine to the second membrane and its important it stays flushed. Spectrapure does sell lower waste systems but they include instructions and test strips on which flow restrictor to use according to how soft your water is and how high your tap TDS is. They also sell a 1:1 UHE system which uses stored DI water to flush and pickle the membrane which I own myself and its fantastic but expensive initially. The cost of ownership over time is much less though since the membrane works better and lasts longer, the DI lasts much longer and the sedimen tand carbon filters last longer since much less wate ris passing through them. Mine paid for itself in 3 years.

 

It also isn't suitable for human consumption.

Mine pipes out and runs into the garden. I actually had a drain installed in my slab specifically for this purpose when we built. So I'm not wasting any of it.

The RO/DI machine will be more efficient the cleaner the water is to begin with. In my case, investing in a house filtration system has save me RO/DI filter money. W/O that or if I bypass it, my RO/DI sediment filters turns dark brown after about 15 gallons. yay well water!