Hey everyone Lana and I are looking into getting a RO unit and I would like some input from all. I understand how they work and why to use one for tank water but our concern is waste. I have read about different RO units but seem to only find feedback on bigger units. Does anyone have a 35gpd unit or smaller that can tell us how they like it. Ours would be primarily used for tank water and possibly drinking water. Even using it for both we could do with a 5 gpd unit but the smallest RO unit I have found is 10gpd. I have seen what appears to be a DI unit that attaches to a faucet that claims to make tap water pure for aquariums but I am suspicious of it actually working the way they claim it does. And finally I know this is a loaded question but if we go with a RO system should we also go with DI as well?
RO/DI questions
- Thread starter brian@sen
- Start date
bneal3
New member
Why chance it? With RODI water you always know what you are getting. Consistently a good source water. We said by crabfan way back.
I purcased a 100gpd because it was just the same price as a 35 gpd. I would recommend a TDS or have your water tested to even see if you need one! Just my 2 cents...
I use waste water to water my plants and yard. I even use it to wash some clothes. I get about 2 waste to every RO/DI gallon!Bruce
I purcased a 100gpd because it was just the same price as a 35 gpd. I would recommend a TDS or have your water tested to even see if you need one! Just my 2 cents...
I use waste water to water my plants and yard. I even use it to wash some clothes. I get about 2 waste to every RO/DI gallon!Bruce
grendl
New member
I dont see a response by crab... am I losing my mind??? AAAAAAAAGGGGH
Anyhow, I would call or contact Bryan Crenshaw at www.purelyH2o.com. He is an RC sponsor, & a helpful fella. I got an amazing system from him. He was very helpful in all aspects of my pruchase, questions, etc. I dont think he has a tiny system like the one you mentioned on his website, but he could tell you what he has, or hwat he can get in that size range.
Anyhow, I would call or contact Bryan Crenshaw at www.purelyH2o.com. He is an RC sponsor, & a helpful fella. I got an amazing system from him. He was very helpful in all aspects of my pruchase, questions, etc. I dont think he has a tiny system like the one you mentioned on his website, but he could tell you what he has, or hwat he can get in that size range.
bneal3
New member
firefish2020
New member
Well I joined the RO/DI club today. got a Pure-Flo 2 RO/DI 50 GPD system. This is my first home unit, if it works as good as the one at the shop I think I will be happy 
phljess
New member
Brian is the filter you're referring to an "aquarium pharmaceuticals" tap water filter. If so, I know someone who uses one and he says it does a good job bringing down TDS in tap water. The only draw back on this filter is its cartridges must be changed much more often than a regular RO/DI filter. But with the small amount of water you would be using, it might not need changed so frequently.
I think Brian is asking more about specific brands/types of small units and the experience owners have had with these units rather than why use RO/DI water. Also, we worry more than most about waste because we have a cistern and Brian hauls water every week to keep it filled. That's enough work without a lot of wasted water. He hauls extra when I need to water my flowers during dry summer periods which is a lot of extra work for him...thanks honey :inlove:
So anyone who has experience with smaller units we would love to hear from you!
grendl, I believe Bryan Crenshaw has answered some questions for Brian and was very helpful.
Thanks,
Lana
So anyone who has experience with smaller units we would love to hear from you!
grendl, I believe Bryan Crenshaw has answered some questions for Brian and was very helpful.
Thanks,
Lana
MattG
Premium Member
I had a kent maximma 35gpd ro/di that was a good quality unit. A bit expensive though for what you get. I really see no difference in the larger units and the smaller units since for the most part they all work the same. The waste water ratio gets a little worse if you step up to the larger units. For the most part you really dont even get more water with the larger units unless you have 'ideal' conditions. (high water pressure, ideal temps,..)
What i would look for in a unit are small prefilters(<= 1 micron) and an adjustable flow restrictor. Most all of the membranes are filmtec so there isnt much of a difference there besides how many gpd. Clear or colored housing is just a preference.
I would go with RO/DI. It really isnt that much more and you will know you are getting the best water you can.
If you use just the DI you will exhaust your resin rather quickly. In the end it will most likely cost you more money replacing the DI resin then if you had just went RO/DI. The RO will prefilter the water before entering the DI prolonging its life.
Right now i am using a www.buckeyefieldsupply.com unit and is who i would recomend for whomever.
What i would look for in a unit are small prefilters(<= 1 micron) and an adjustable flow restrictor. Most all of the membranes are filmtec so there isnt much of a difference there besides how many gpd. Clear or colored housing is just a preference.
I would go with RO/DI. It really isnt that much more and you will know you are getting the best water you can.
If you use just the DI you will exhaust your resin rather quickly. In the end it will most likely cost you more money replacing the DI resin then if you had just went RO/DI. The RO will prefilter the water before entering the DI prolonging its life.
Right now i am using a www.buckeyefieldsupply.com unit and is who i would recomend for whomever.
I purchased mine after Matt gave his suggestion about two months ago from buckeyefieldsupply. I love this unit, I got the 100gph, I get about 3 gallons an hour. It has made a world of difference in my tank, the water is crystal clear and I don't have the algae I used to. I'm really glad I didn't get the smaller unit. You will use the same amount of water and have the same amount of waste no matter what size you get, the waste will depend on how much water you need to fill your tank and not on the size of ro/di unit. IMO I feel that in your case it would be better to simply purchase your water, either from a store or from JoeMars or you LFS.
H.crispa
New member
Hmmm.... Finally a topic I actually DO know something about. Most of the time I just make stuff up 
Here are my thoughts:
first, get a unit that is rated for at least tripple of what you think you need. When you have an RO, you tend to find other uses for it like cooking, drinking, etc. and even if you only need 10GPD, a 100GPD unit makes that 10 gallons a lot quicker than a 10 GPD unit. You will always wish you had gone bigger if you don't do it right off the bat. Also, when an emergency crops up, it is soooooooooo nice to be able to whip up a bountiful batch of RO water in a jiffy.
Second, I doubt there is much difference in the end product between brands when you compare apples to apples. Don't compare a TFC membrane to a cellulose membrane. Just make sure you get a well-made unit from a supplier with a good reputation. RO units are dirt-cheap compared to 10-15 years ago. Get a unit with a good TFC membrane that can be changed easily as you will need to do this every few years... at least that is the convetional wisdom. My unit is 10 yrs old and still performing top-notch on the original membrane!
Third, look at how it is constructed. Most units have 2 or 3 canisters hanging down. A typical set up would be a sediment prefilter, then a carbon block, then the RO membrane, then possibly a DI resin canister. This unit should give you lab-grade water or something close. With a unit that has 2 or 3 canisters, you can "customize" your set up to a degree. And for heaven's sake, try to get a unit that you can use aftermarket canister refills in. You don't have to use the aftermarket stuff and you may not want to-- but the mere presence of competition keeps the genuine refill suppliers honest...(read that as "cheaper").
Fourth, figure out where you are going to keep you resivoir!!! Yes, you need one! Don't even try the "buckets-in-the-floor-as-you-need-it" method! That only leads to a lot of work and inconvenience and yes, WET FLOORS!!!!! Overflowed buckets! P.Oed spouses! You name it. A simple 20 long can save you many headaches-- and sleeping on the couch! Which brings me to my final point.
Fifth, you need a float switch or a timer! Do not underestimate the value of this component!!!! Until you have mopped up 20 gallons of overflow (several times) and slept on said couch because of the afore mentioned overflow (several times), you can not fully appreciate a device that SHUTS THE SUCKER OFF AUTOMATICALLY! Personally, I have a garden watering timer that I can set for 5, 10, 30, 60, 90, or 120 minutes and after a trip to Lowes for some adapters, it works PERFECTLY!.....And I get to sleep in my cumfy, cozy bed with a non- P.Oed wife.
Here are my thoughts:
first, get a unit that is rated for at least tripple of what you think you need. When you have an RO, you tend to find other uses for it like cooking, drinking, etc. and even if you only need 10GPD, a 100GPD unit makes that 10 gallons a lot quicker than a 10 GPD unit. You will always wish you had gone bigger if you don't do it right off the bat. Also, when an emergency crops up, it is soooooooooo nice to be able to whip up a bountiful batch of RO water in a jiffy.
Second, I doubt there is much difference in the end product between brands when you compare apples to apples. Don't compare a TFC membrane to a cellulose membrane. Just make sure you get a well-made unit from a supplier with a good reputation. RO units are dirt-cheap compared to 10-15 years ago. Get a unit with a good TFC membrane that can be changed easily as you will need to do this every few years... at least that is the convetional wisdom. My unit is 10 yrs old and still performing top-notch on the original membrane!
Third, look at how it is constructed. Most units have 2 or 3 canisters hanging down. A typical set up would be a sediment prefilter, then a carbon block, then the RO membrane, then possibly a DI resin canister. This unit should give you lab-grade water or something close. With a unit that has 2 or 3 canisters, you can "customize" your set up to a degree. And for heaven's sake, try to get a unit that you can use aftermarket canister refills in. You don't have to use the aftermarket stuff and you may not want to-- but the mere presence of competition keeps the genuine refill suppliers honest...(read that as "cheaper").
Fourth, figure out where you are going to keep you resivoir!!! Yes, you need one! Don't even try the "buckets-in-the-floor-as-you-need-it" method! That only leads to a lot of work and inconvenience and yes, WET FLOORS!!!!! Overflowed buckets! P.Oed spouses! You name it. A simple 20 long can save you many headaches-- and sleeping on the couch! Which brings me to my final point.
Fifth, you need a float switch or a timer! Do not underestimate the value of this component!!!! Until you have mopped up 20 gallons of overflow (several times) and slept on said couch because of the afore mentioned overflow (several times), you can not fully appreciate a device that SHUTS THE SUCKER OFF AUTOMATICALLY! Personally, I have a garden watering timer that I can set for 5, 10, 30, 60, 90, or 120 minutes and after a trip to Lowes for some adapters, it works PERFECTLY!.....And I get to sleep in my cumfy, cozy bed with a non- P.Oed wife.
Similar threads
