Need Most Efficient RO System for Small Grow, @ 10 Gallons Per Week

[Vernal Equinox]

I'm soon to be running two 20 gallon bio-tubs (ala-NIMBY), and looking to setup a small RO system that doesn't have a crazy 4-1 (or worse) waste to water ratio. After initial tub fill, I think I'll only need 10 gals or so per week for top offs (running a cab with four 150 watt HPS). I love the bio-tub setup using RO water because it's so simple, and I never need to adjust ph (as in NEVER) or do reservoir changes.

So, any suggestions on a super-efficient RO system? I'm debating whether or not to just do 25 cent refills at the store, as between the high cost of water/sewage in my area, it would be a wash! I do think I could discreetly get 10 gallons into the house every week though, but there are nosy neighbors on every block.

BTW, I try using the search function before every new thread, but the results I get are always hit-or-miss.

 

[negative37dBA]

Are your water rates high enough that 40 gallons of h2o a week is to much? Thats taking into account the 4/1 ratio. How do you afford a shower? I would NOT haul water. Big hassel..Iv'e done it... much more gallonage than you are talking and it is a pain.
You can easily search the web for low ratio RO systems but the amount of water that you are talking about seems to small to warrant the fuss.
I installed a simple 25 GPD RO system and it was around $120.00. Great investment.

Link to my grow diary.
https://www.icmag.com/ic/showthread.php?t=235661

 

[SeaMaiden]

Research lower waste ratio units. I learned that pressure and water temperature can play a big role in how much waste water is generated (which I still use, btw, because it's still "cleaner" than what went in). I use a permeate pump, but do not heat the water coming into the unit. Water pressure and condition also determine flow rate and waste, you may need to prefilter using a sediment/mechanical filtration method.

I got an RO/DI unit+permeate pump for around $120 at purewaterclub dot com. Can't say it's the best quality unit, but they have decent customer service and it gives me the water I'm after. Hooking it up and stuff can be a bit of a PITA.

 

[Vernal Equinox]

Are your water rates high enough that 40 gallons of h2o a week is to much? Thats taking into account the 4/1 ratio. How do you afford a shower? I would NOT haul water. Big hassel..Iv'e done it... much more gallonage than you are talking and it is a pain.
You can easily search the web for low ratio RO systems but the amount of water that you are talking about seems to small to warrant the fuss.
I installed a simple 25 GPD RO system and it was around $120.00. Great investment.

The cash isn't the issue with the water...the delta on the bill is, as I share water bill with another unit in the building. The water bill isn't the bad thing...it's the freaking sewer bill that kills.


I'll check the link SM...thanks. What I've been reading in my research so far, however, is that there is a big difference in advertised ratios vs. actual ratios, especially with budget units (according to actual reviews).

 

[SeaMaiden]

Ok, well, since you mentioned "bio-tubs" I'm gonna throw another possibility out there at ya. Filtration through peat moss using an aquarium filter. It likely won't really reduce EC (don't know that it could be all that easily measured), but it does reduce alkalinity and pH in a manner that delicate FW fishes find quite livable.

 

[habeeb]

^ from what I understand, sewer charges are mandatory? you can't avoid paying those, and your only playing for water used???

if so it's not much water used either way.. you can catch 'waste' water to use for cooking, or anything you can think up



R/O is the way to go most of the time.. mineral flux in water supply, coupled with alot of metals, also it's nice to have a starting point of zero... makes things easier to manage / diagnose / understand..

 

[dramamine]

Research lower waste ratio units. I learned that pressure and water temperature can play a big role in how much waste water is generated (which I still use, btw, because it's still "cleaner" than what went in). I use a permeate pump, but do not heat the water coming into the unit. Water pressure and condition also determine flow rate and waste, you may need to prefilter using a sediment/mechanical filtration method.

I got an RO/DI unit+permeate pump for around $120 at purewaterclub dot com. Can't say it's the best quality unit, but they have decent customer service and it gives me the water I'm after. Hooking it up and stuff can be a bit of a PITA.

I've heard you say before that the waste water from RO is cleaner than the original source water. Maybe I have an anomaly on my hands, but my source water is .3 EC , and my waste from RO is .5...consistently.

edit: ....everything I've read says that RO waste water carries off a majority of the filtered material.....it's even referred to as the "concentrate". What unit do you run and how clean is your waste water?

 

[Scottish Research]

Check out Spectrapure. They have the best deals around. Every month they have specials.

R.Fortune

 

[SeaMaiden]

I've heard you say before that the waste water from RO is cleaner than the original source water. Maybe I have an anomaly on my hands, but my source water is .3 EC , and my waste from RO is .5...consistently.

edit: ....everything I've read says that RO waste water carries off a majority of the filtered material.....it's even referred to as the "concentrate". What unit do you run and how clean is your waste water?

I run an RO/DI unit, 6-stage. The water coming in is around a .5-.6 EC, and coming out it's a lot closer to .1. This is water that's passed through a whole house 'filtration' unit (I'm using that term loosely, it is the most basic of filtration types and levels).

Now I wonder if I've got it hooked up whonky or something, but it came pretty much put together already, just hook it up and go. Or could it be the overall quality of the unit itself..? Maybe that explains why I needed to change out filter units and resins after just a few months of use.

I need to qualify that I haven't actually run my unit for over a year now except to make water for my steam mop thingy. Been growing outdoors only, using unfiltered well water for the irrigation.

 

[dramamine]

I run an RO/DI unit, 6-stage. The water coming in is around a .5-.6 EC, and coming out it's a lot closer to .1. This is water that's passed through a whole house 'filtration' unit (I'm using that term loosely, it is the most basic of filtration types and levels).

Now I wonder if I've got it hooked up whonky or something, but it came pretty much put together already, just hook it up and go. Or could it be the overall quality of the unit itself..? Maybe that explains why I needed to change out filter units and resins after just a few months of use.

I need to qualify that I haven't actually run my unit for over a year now except to make water for my steam mop thingy. Been growing outdoors only, using unfiltered well water for the irrigation.

I dunno, it does sound like most of your sediment is collecting in your filter/membrane. I've been thinking about adding a pump to boost my pressure going in. As I understand it, the benefit should be less material collected in the membrane, as it is carried off more efficiently in the waste water. I expect this to increase the lifespan of the membrane, and deliver a smaller volume of more concentrated waste water.

 

[SeaMaiden]

Oh! I forgot to mention I have a permeate pump preceding the whole unit. But based on what you're saying, if the permeate pump I'm using is increasing efficacy/efficiency, I should have observed a waste water that's worse than what's going into the unit, yes? Now I wonder if I'm doing something wrong. I'm getting the low-to-no EC water I was after from the unit.

 

[Funion]

Berkey gravity water filters.