The one named Inception? https://tanninaquatics.com/blogs/the-tint-1/genesis
if you ensure adequate (but not too high) water pressure and slightly restrict the outflow, you can safely get the reject ratio down to about 1:2.5 or 1:3. Although you can technically get it down to 1:1, it's not economical to do so, and not recommended.The one thing that stood out for me in the article you linked was this bit: "Pretreating water with an RO unit can, depending on its efficiency, use quite large amounts of water with RO to wastewater ratios of up to 1:5! So if you live in areas with regular droughts, high water hardness and/or high prices on tapwater you might want to overthink this."
They claim otherwise.... but the unit is pricey.It's technically possible to go to 1:1, but unless you have zero hardness it will drastically reduce the life of your membrane. For example, if you run a second membrane at the waste line, you'll have an extremely high TDS going in. It's going to get awfully expensive to keep replacing that membrane. Not to mention you'll need to run higher pressure to get the water through two membranes. Anything over 75psi could compromise the housing, which will be a huge mess.
The other way to do it is to put a very low flow restrictor at the outlet, which creates similar problems.
Since I'm not wasting any of the water, I'd rather give up some efficiency to reduce the overall cost (by a lot). That's my advice, anyway.
They do have a vested interest in claiming otherwise... You can read more in the reef forums, including Russ Romme, who sells RO units himself and could easily sell this arrangement. Since there's nowhere else for the ions to go besides the membrane, I don't see how you can get around the lifespan issue. But I would be happy to be proven wrong.They claim otherwise.... but the unit is pricey.
I thought about trying to reuse water from the aquarium (water changes) since the amount will be around 1000 gallons a week but the headache of rerouting it to the sprinkler system or similar was quite significant and I was advised to not do it.
Setting up a pair of 450 gallon aquariums and 4 other 100 gallon aquariums. I figure if i want a community; i should give folks a bit of room to stretch out. Sizes are 10x4x22,8x4x22,4x4x20,4x4x18,6x2x18,6x2x18 (l-ft,w-ft,h-inch). Also having fewer tanks require less work to cleanThey do have a vested interest in claiming otherwise... You can read more in the reef forums, including Russ Romme, who sells RO units himself and could easily sell this arrangement. Since there's nowhere else for the ions to go besides the membrane, I don't see how you can get around the lifespan issue. But I would be happy to be proven wrong.
Oh my. I can see why you'd rather optimize for reducing the ratio. I don't have nearly that much volume, 67.5 gallons total across 6 tanks. There are straightforward ways to use the reject water (washing machine, toilet) but probably not putting a very big dent in 1000 gallons.
Why don't you go for a DI-unit? I use one for many years now and I'm quite happy with it.The one thing that stood out for me in the article you linked was this bit: "Pretreating water with an RO unit can, depending on its efficiency, use quite large amounts of water with RO to wastewater ratios of up to 1:5! So if you live in areas with regular droughts, high water hardness and/or high prices on tapwater you might want to overthink this."
I'm curious is there a difference between di water and ro water ? If not why would a di unit be more efficient than a ro unit; why not just make a ro unit like a di unit ?Why don't you go for a DI-unit? I use one for many years now and I'm quite happy with it.
Ah, I see. Each system has its pros and cons. I get pretty much the same result, as I have an EC in the tap of only about 200µS/cm and good pressure on the tap. The waste ratio is close to 1:1.@MacZ I use this mixed bet resin: https://www.purolite.com/product-pdf/MB400.pdf
It removes "everything", my tap water has an EC of about 700uS/cm and with fresh resin the DI water is <5uS/cm.
I have a faucet in the kitchen from where I pass the water through a hose to my fishroom with the DI-unit and into my 220L water drum. Of course I could also pass the waste water of an RO-unit back into the kitchen. But with my extremely hard tap water and the output of a common RO-unit, it would probably take very long to fill my 220 liter water drum. And my wife would certainly not be amused if two hoses run through our flat and the kitchen faucet can't be used for many hours...@Frank Hättich since you don’t have a water outlet, are you using a pump to circulate water through the resin?
100 gallons (450 liter) a day??? How many tanks do you have? With your tap water you should get about 250 liter (66 gallons) of 50uS/cm (TDS 32ppm) water from 1 liter of resin.So my tap is 130TDS/gh 7/kh 3 - am i better off with DI or RO? Also I need about 100 gallons of ro water a day (when i did a quick search i saw no di unit what that kind of output) ?