Will I benefit from the brs 150gpd dupgrade?

[Fishbike13]

I purchased a 4 stage 75gpd system before i knew a lot about my tap water, but since i have run this unit i have found that my tap water is around 150tds, and 80psi static pressure. The test strips that came with the unit indicated an almost unmeasurable low level of total and free chlorine.

After the sediment and carbon blocks on my rodi unit, the tds meter indicates between 5-8 tds going into the membrane, with 0 coming out, does this sound right?

My thought process is that with relatively low tds i would be able to make a lot more water with less waste and reasonable membrane life. How wrong am i? Thanks!

 

[WVNed]

I did the upgrade on my 4 stage and it does what it is supposed to. Makes water faster.

0 coming out is what you want.

 

[KStatefan]

A dual membrane setup is more efficient on water usage and prefilters and less efficient on DI resin.

Instead of 5-8 tds going into the membrane i would think that is coming out of the membrane and the 0 TDS is coming out of the DI resin

 

[Fishbike13]

A dual membrane setup is more efficient on water usage and prefilters and less efficient on DI resin.

Instead of 5-8 tds going into the membrane i would think that is coming out of the membrane and the 0 TDS is coming out of the DI resin

Yes thats what it is. For some reason i had it mixed up. That 5-8 seems to creep down and hang out at 3-4 the longer i let it run.

Seeing as i only have a 40 gallon tank that i am setting up, i think i will go for the water saver. Id rather replace the resin a month or two earlier, rather than throw out hundreds of gallons of water. Eco friendliness is a different debate, i just dont like to see that much waste haha.

 

[WVNed]

Consider adding a permeate pump. It increases the efficiency of the filter so it produces at 1 1:1 ratio instead of 1:4.

 

[Fishbike13]

Consider adding a permeate pump. It increases the efficiency of the filter so it produces at 1 1:1 ratio instead of 1:4.

I like the idea, however some searching shows that a permeate pump is designed for use on drinking water storage tanks and would not be effective on an RO/DI system that does not use a pressurized storage tank. With my tap at 80psi, and BRS warning against pressures beyond 90 psi, i don't think that i would get as much product water yield for the cost of a pump, versus the water saver kit.

I more or less created the thread in the event that my tds was too high or low to really fully benefit from a water saver kit.

 

[JoshH]

I would be concerned about your current membrane, how old is It? 3-4 TDS is pretty high for 150 TDS going in. Aside from that, with 150 TDS from your source I would say you definately will benefit from a Water saver upgrade.

 

[WVNed]

I am using one.
Using 2 identical drinking glasses my unit fills one with filtered water and one with waste water in the same time.

My filter makes 6 gallons an hour at 1:1 with the second membrane and the permeate pump upgrades.
It is running right now in the kitchen. It is water change day.

 

[KStatefan]

The permeate pump does not control the ratio the flow restrictor does.

 

[Fishbike13]

I would be concerned about your current membrane, how old is It? 3-4 TDS is pretty high for 150 TDS going in. Aside from that, with 150 TDS from your source I would say you definately will benefit from a Water saver upgrade.

the whole unit is new, ive only made 5 gallons with it so far, i ran it for about an hour to flush the carbon etc per brs instructions before making any useable product water, and if i let it run longer it may fall lower but i only used it for an hour to make the 5 gallons.

 

[chipmunkofdoom2]

Consider adding a permeate pump. It increases the efficiency of the filter so it produces at 1 1:1 ratio instead of 1:4.

I personally wouldn't do this. You need to maintain a waste to product ratio around 4 to 1 to keep your membrane clean. An RO membrane works by concentrating all of the solids from your source water into the waste water. Without running a proper waste water ratio, the membrane is unable to get rid of those solids. The solids build up on the membrane and clog the pores, severely shortening the life of the membrane.

If you do want to do this, you don't need an expensive permeate pump. Simply buy a flow restrictor with a lower rating. That will force more water through the membrane by allowing less to go down the drain. As I said, I wouldn't do this, but if you wanted to, you can do it for much less than the cost of a permeate pump.

 

[Fishbike13]

I am using one.
Using 2 identical drinking glasses my unit fills one with filtered water and one with waste water in the same time.

My filter makes 6 gallons an hour at 1:1 with the second membrane and the permeate pump upgrades.
It is running right now in the kitchen. It is water change day.

I was just going off the common use for a permeate pump, i will have to look into it further.

 

[Fishbike13]

I personally wouldn't do this. You need to maintain a waste to product ratio around 4 to 1 to keep your membrane clean. An RO membrane works by concentrating all of the solids from your source water into the waste water. Without running a proper waste water ratio, the membrane is unable to get rid of those solids. The solids build up on the membrane and clog the pores, severely shortening the life of the membrane.

If you do want to do this, you don't need an expensive permeate pump. Simply buy a flow restrictor with a lower rating. That will force more water through the membrane by allowing less to go down the drain. As I said, I wouldn't do this, but if you wanted to, you can do it for much less than the cost of a permeate pump.

Yes, this is what i was getting at when i asked about the water saver. I understand that a water saver may reduce the life of the membrane, but I am not going to be running a 300 gallon reef, just a 40 breeder so if the difference in flush water only equates to a month shorter life of the membrane with vs without the kit, then that is a sacrifice i am willing to make. The main goal behind it is to shorten the amount of time i have to be home with the RODI unit running to get the same amount of water, that and i wont feel as guilty about the amount of waste water going down the drain.

I do plan to keep a 50g drum filled with waste water for the mulch beds outside the house, but i will still be producing waste faster than i use it.

 

[chipmunkofdoom2]

@Fishbike13 Why is the amount of time the unit is on while you're home important? Don't you have a float valve that will shut off the unit when your RO reservoir is full?

Also, I personally wouldn't feel guilty about the water going down the drain. The average family of 4 in the US uses between 9,000 and 12,000 gallons of water a month. If you need 100 gallons of deionized water and you run a 4 to 1 waste to product ratio, you're wasting 400 gallons of water a month. That's less than five percent of the average family's monthly water usage. Even if you cut that in a third, you're only reducing your household water usage by 3%. With a 40 gallon breeder, it's unlikely you'll need 100 gallons of DI water. Maybe only half of that or so.

 

[Fishbike13]

@Fishbike13 Why is the amount of time the unit is on while you're home important? Don't you have a float valve that will shut off the unit when your RO reservoir is full?

Also, I personally wouldn't feel guilty about the water going down the drain. The average family of 4 in the US uses between 9,000 and 12,000 gallons of water a month. If you need 100 gallons of deionized water and you run a 4 to 1 waste to product ratio, you're wasting 400 gallons of water a month. That's less than five percent of the average family's monthly water usage. Even if you cut that in a third, you're only reducing your household water usage by 3%. With a 40 gallon breeder, it's unlikely you'll need 100 gallons of DI water. Maybe only half of that or so.

I do not have a float valve to turn it off, nor do i think i will trust one while i am gone. I live alone, and im gone for 14 hours a day for work, and that is plenty of time for even the slow flow of an RODI unit to do some damage should it flood. Id like to be able to turn it on for a few hours a couple days a week.

Ive recently gone through some water related issues with water main leaks and flooded crawlspaces, so that is the base of my trust issues with running water while im gone.

You do make a good point about the waste water though, maybe i will hold off on the water saver until after i get the tank up and running. The money can be used better elsewhere.

While this ultimately makes the thread moot, i did learn a little bit. So far, i love the turnaround on this forum, very active.

 

[WVNed]

Left is product water and right waste

TDS meter says 2 and 0 for in/out. 80psi from the tap

I am using the original flow restrictor.

I am not smart enough to know why it works but I can see it does.

 

[JoshH]

I do not have a float valve to turn it off, nor do i think i will trust one while i am gone. I live alone, and im gone for 14 hours a day for work, and that is plenty of time for even the slow flow of an RODI unit to do some damage should it flood. Id like to be able to turn it on for a few hours a couple days a week.

Ive recently gone through some water related issues with water main leaks and flooded crawlspaces, so that is the base of my trust issues with running water while im gone.

I feel this thread has gotten blown way out of proportion. @Fishbike13 there is absolutely nothing wrong with your plan to add a second membrane. There is no need for an additional pump as 80 PSI is more than sufficient to run dual membranes. Two membranes will get your OVERALL production to 1:2 all you will need is an appropriate restrictor for the second membrane and you are good to go.

 

[chipmunkofdoom2]

I do not have a float valve to turn it off, nor do i think i will trust one while i am gone. I live alone, and im gone for 14 hours a day for work, and that is plenty of time for even the slow flow of an RODI unit to do some damage should it flood. Id like to be able to turn it on for a few hours a couple days a week.

Even if you don't trust the RO/DI unit to be on while you're gone, I'd still get a float valve. I ran this system for years, where I had to manually shut off the water when my reservoir was full. I can't tell you how many times I flooeded my condo because I forgot to turn the water off, and I was home those times too. I think over time you'll begin to trust a float valve more. They work very well for being so simple, and a very high number of hobbyists use them without issue.

Another option is to add an emergency drain to your RO/DI reservoir and plumb it to a drain in your home. If your float valve fails and the water keeps going after the shutoff point, eventually it will get to your emergency drain and flow right down the drain as opposed to all over your floor.

 

[Fishbike13]

Get a water saver kit, and a float valve because it'll work faster, and there's a high possibility of me forgetting that i have it running. Appropriate summary?

It may have gotten more involved than i planned, but i enjoy the discussion when i can learn more about WHY something works, or doesn't work, rather than THAT it happens.

 

[chipmunkofdoom2]

Get a water saver kit, and a float valve because it'll work faster, and there's a high possibility of me forgetting that i have it running. Appropriate summary?

It may have gotten more involved than i planned, but i enjoy the discussion when i can learn more about WHY something works, or doesn't work, rather than THAT it happens.

I would go for the float valve, yes. I don't like the dual membrane setup very much in general, so I would not personally get that. The hobby really seems to like the watersaver upgrade though, so I'll definitely get outvoted on that one. But, regardless of how little my vote counts, I submit it anyway.