Making your own RO?

[ReefNewb]

I found this ro/di system (http://www.bulkreefsupply.com/store/products/reverse-osmosis-filters-and-systems/reverses-osmosis-deionization-systems/standard-ro-di-systems/75-gpd-ro-di-5-stage-standard-system.html) and was wondering, is it this easy to make your own ro? i was under the impression you had to have huge tanks and expensive filters and alot of time to make ro. Is it as simple as plug and play? or is there a bunch of extra stuff needed? and is it cost efficient, or just for these huge 200+ gal tanks? Is anyone doing this? Thanks

P.S. For now i just have a 55gal fowlr and maybe soon a 29-35gal reef...

[prof]

Yup, that is all it takes.

RO actually describes just one of the 5 stages of that unit. The usual set up is sediment filter - carbon filter - reverse osmosis membrane - de-ionization... Two or more carbons and/or sediments will extend the life of the RO membrane.

[Derek]

It is super easy and will save you a boat load of cash.

[+Eckreef]

I have been using the same BRS unit for almost a year and it works great. I use it for a 57 g tank and just run it a couple times a month to get 20 gal of water or so for topoff and water changes.

[The_Colonel]

I have an RO/DI system for my 28G nano. Besides using for the tank, I never need to buy bottled drinking water. (Just make sure you get a RO bypass if using RO/DI, that way you have plain RO water for drinking.)

[caferacermike]

I make Kool-aid and ice with my RO/DI water. Ice comes out crystal clear instead of white, and you have to use less sugar in RO/DI as it won't mix in at 2 cups.

It is that easy, but it isn't. I'm going to tell you right now that 75gpd is sloooooow. Folks for some reason always think that 75 is all it can produce and for some reason it ought to do that in like 20 minutes. It does not. Simple math says it should make 3g PER HOUR. I don't have that kind of time, maybe you do, if so I wish I was as well off financially as you are. Nope instead I have to work for a living. What am I going on about? You will need some kind of large vessel to contain your ready to go water. If you do a water change, say suck out 20g and expect to hook up your apparatus to a trash can with some salt in it, well let's say your tank will be very low for a couple of days while you wait for your mixing can to fill up. On another note, all kinds of things will affect your production rate, most will tell you it's not even close to the stated amount. Temperature, hardness, pressure, and other such items can slow it tremendously. All the more reason to do it right when you do set it up.

Minimum set up (IMO):

75gpd RO/DI unit.

3 extra sediment filters

3 extra carbon/chlorine filters

1 extra RO membrane

enough DI resin to make up 2 10" filters (isn't that about 5 lbs?)

20-50g or even larger barrel for clean water storage

float valve, timers w/solenoid, or some other device to help maintain that storage tank.

Auto shut-off valve to work in conjunction with your float valve.

extra tubing

Dual TDS meter.

Pressure gauge either built onto the unit or installed before the unit.

Filter housing wrench.

Extra 10" filter housing.

Reasons:

75gpd is an ideal unit. The lower the number, the purer the RO water.

Generally your pre-filters wear out at a ratio of about 3:1. Keeping spare filters is always a good bet. To expensive to pay for shipping to buy them only when you need them. Also such a hassle to run out.

Same goes for DI resin. Such a hassle to buy just a little.

You will want some sort of container to hold your water until you use it. You can run an ATO (Auto top-off unit to your tank to stop those dreaded daily refills) from it, and you can have plenty of water handy for when you do water changes. If you have it on a float or some other mechanism it will automatically refill itself. Do a quick search on how many times people here have flooded a garage, kitchen, or clothes washing room because they refill manually and forgot to turn off the water supply. Why do $2,000 worth of damage for the lack of $20 in parts?

Extra tubing? Goes without saying. You'll need it as you plumb everything together. Then you'll want some more, I promise.

Dual TDS meter? Yep. By placing one just passed the RO membrane and the other side coming out of your DI resin you can monitor the performance of your membrane and resin. If the resin side goes up before the membrane, it is time for new resin. If the membrane side climbs up, it is time for a new membrane. Before setting everything up, you can sample your incoming water to see how high your TDS actually is. Expect readings of 350-600+. Look for below 20 from your membrane and 0-5 from your resin.

A pressure gauge before the unit will help you decide how well the unit can perform. You may not need it all the time, but it can come in very handy when you set the unit up the first time. I was having problems with a unit when I lived downtown because my pressure was 120PSI, they are best run right at 80PSI. It's not life or death, but when they run about $6-10 just get one.

Why a housing wrench? Why to prevent leaks and because they are such a pain to open later.

Oh and finally my favorite, an extra filter housing. All you need is the bottom part. Many of you are thinking I'm crazy for mentioning it. I believe I recall Callahan once freaking out looking for one, I know for a fact that several members have broken one and it put them in a bind for awhile. Since they are made of plastic and can break at any time, it's just a good idea to keep a spare.

So yeah it is "easy" but to avoid the headaches that we've all had from ours, do it right the first time. Also search the forum threads. There are hundreds of topics about this. There are several great methods that we've all shared. I am really proud of my 125g storage tank that is 4' off the ground. When I need water I open a 1 1/4" ball valve and fill up a 50g barrel in about 60 seconds. There are other good methods on smaller scales, you'll find something that will seem right for your needs.

[caferacermike]

It is super easy and will save you a boat load of cash.

I tend to disagree. I will agree with the statement that it is easy and could save you some money. I won't say it will save you a boat load of cash, ever.

Pros I will make towards buying your water ready to go.

It is simple, ready to go.

It is super cheap, most shops are about 5g for $1.

Window shopping opportunities.

Bring in your tank water for a free sample testing every week.

Cons

Heavy lifting.

Possible spending of sacred cash on other items at the store.

I don't think for a minute that my RO/DI unit is cost effective versus buying water for my 75g tank. I only bought my unit when I bought a 400g tank. I actually enjoyed going to the shops once a week with 5 jugs to fill while looking at the for sales and BS'ing with the Keepers. I found that most of the time, since I was always buying something else, that my water was free. Awesome. I never had any headaches associated with maintenance of an RO/DI nor did I have the costs associated with ownership.

Keep in mind that you can easily spend $200 on the unit and another $200 on accessories. For $400 I can purchase 2,000g of water from the LFS. For a smaller tank like a 75g, that's like all the water you would need for a year of evap (@2g a day) and a 25g water change every week for a year. Yes I did the math if you want to make a challenge. Or basically almost all of your water needs for 2-3 years. Add in the fact that you will probably average $100 a year in filters, and well you can see how this adds up over the long run. So with the fact that you can get quality, hassle free, water at the store (IE: let them change out the filters and resins on their dime) for about the same price as setting up your own unit, it can actually make sense to buy it.

I bet most of you spend the $30 every other week for someone else to mow your lawn don't you. Yep. You could spend $1,000 buying a small mower, weed eater, edger, blower, etc.. and with the yearly expenses on maintenance and gas or you could just get your lawn mowed about 33 times instead. It seems like hiring someone to do it for you would actually be more expensive, but if you factor in the true costs associated with it and your time, some people are better off paying to have it done.

That reminds me, ugh, I need to leave now and mow my lawn.

[Erik!]

LOL Mike, I have so missed your sarcasm and truthiness. Did you do the math on the lawnmowing part? You may want to get a pedometer and double check. Or get two just to ensure accuracy!

Tab and I say hello, and again, thanks for showing us cool local spots to take pictures; we really enjoyed that day.

[Derek]

For me it worked out. I do 15 gallon water changes each week. I ended up being much cheaper for me to get an RO/DI unit and mix my own salt. I was spending like $120 a month just on water.

[caferacermike]

Oh now you didn't say anything about buying premixed salt. Yeah that's the devil.

[caferacermike]

So wait.................

Are you saying you paid $60 a month on pre-mixed and then bought 300g of top off water each month? I'm kinda not buying that.........

I mean like those guys on the Acura commercial, there are excuses for luxury and then there are reasons.

$120 a month on water sounds a bit to much to believe. I'm going to believe you because you said 'tis truth, but I mean, like I'm just sayin...........

[caferacermike]

Oh and like I always say here, are you comparing apples to apples, or apples to oranges?

Like I said in my detailed reply, that I find my RO/DI handy but a tad excessive for a 75g tank, our Post Author is asking about this for a 55g.

55g:75g= apples to apples.

55g:185g= apples to oranges.

Note that I did address that in my reply. I was trying to help out the person asking about their tank.

[Derek]

So wait.................

Are you saying you paid $60 a month on pre-mixed and then bought 300g of top off water each month? I'm kinda not buying that.........

I mean like those guys on the Acura commercial, there are excuses for luxury and then there are reasons.

$120 a month on water sounds a bit to much to believe. I'm going to believe you because you said 'tis truth, but I mean, like I'm just sayin...........

I was buying anywhere from 15 to 25 gallons of pre-mixed saltwater a week at $1.25 a gallon. For 15 gallons a month that is $75.00 plus tax. I was also buying 10 gallons of RO each week at $0.25 a gallon. I rounded up. Either way, buying pre-mixed gets pricy if you are buying it once a week.

[ReefNewb]

Mike i beleive it is. Thank you very much for the detailed info. Ill have to look into this ro a bit more. But if my gf gets her way (often) we will have 20 different tanks and im sure onewill be a 200g. lol. And i enjoy the sarcasm and analogies. Thanks again to all involved in my search for ro mking

[NonSequitur]

Mike's right about the production rate and need to store water, that's why most drinking water systems come with presurized storage tanks.

These actually come in handy for aquarium use as well, if you have room for them. I have 2 3gal pressurized storage tanks connected to my 24gpd system, which provide plenty of on-demand water for drinking, making coffee, top-offs, etc. For storage of larger volumes I run the DI output into a 5gal bucket with a float valve, which I pour into a brute trash can. This way I can produce 5-10gal of aquarium water in the evening after everyone else goes to bed and still have drinking water in the morning (keeps the rest of the family happy)

In all honesty, I've probably spent more on my water system than I would if I just bought the water at the LFS, but the convenience factor of always having water available (with a little pre-planning, anyway) won out in my case.

Another small benefit of running your own RO: You can capture the concentrate (waste) water from the membrane and use it to water your plants .

[prof]

A RODI system is plug and play. All you need is a water supply and a drain.

Ok, yes, you will also need a container to hold the RO/DI water. A small trash can or other plastic bin and a float valve will keep you from haveing to manually monitor the making of your water.

For years now I have relied on a 100gpd system connected to a 30g brute trash can on wheels.

100gpd RODI - $150-200

Trash can and wheels - $40

Float valve - $15

Extra tubing - $10

Misc. fittings - $10-20

Extra pump and an old python siphon hose - $50-100

So, on the high end it is close to $400 in equipment and that does not cover upkeep. But I run close to 800 gallons in 3 seperate systems... I would not live without it and I never carry water anymore!

If you are frugal you could put together a similar system for less than $200. Just use a lower gpd system and shop wisely for your accesories.

You don't have to keep extra filters on hand. Just keep a couple of water jugs handy. If something goes wrong with your system you can always fall back on the LFS for water.

Mike's system is great. Find his thread on auto-topoff. That is the way to do it! His method may border on extreme but you will never hear him post about how his cheap plastic bucket cracked or how his repurposed toilet repair parts are failing. His complaints are going to be about how his digital timers are more difficult to setup than an 80's era VCR

[+Lamont]

I also believe that RO/DI system would not be cost effective for tanks under 100g's. I have a 75g tank and do weekly water changes of 5g's. I used to buy the water from aquatek and then buy salt which would cost $25. After months of that I decided to just buy premixed water from Fishy Business for just $1 a gallon.($20 a month) Shane at Fishy Business also adds other stuff to his water to help corals and fish, so I cut back on my dosing also. Which save me from using up my chemicals so quickly. I only use about a gallon a day for top off and that adds up to $5 a month. So I only spend $25 a month on all my water needs. This way just makes more sense to me.

[renman303]

I'm the rebel here. I no longer use my RO portion of the RO/DI. I run through the DI portion only with Phosban and Carbon and straight into the mix...no issues in over a year. Those cartridges are ridiculously expensive and you waste about 10 times the water that you actually use as RO. I've learned to do so much of this hobby in a more natural way.

[TexasTiger]

I have a 75g RO/DI hooked up to my hose in the backyard and I love having water on demand. I didn't like the hassle of going to get water, but I'm kind of lazy. I just use 5 gallon jugs, no auto top offs or big storage bins (yet). Sometimes I overfill them a bit, but all in all this low tech method works fine for now.

[JasonJones]

This is an interesting thread. I have had RO units for years and I have never once thought they were overly complicated or too much of a hassle.

Does it take time to make water, yes. It takes 20 seconds for me to walk over and open the valve to the unit. It then takes me another 10 seconds to set the alarm on my phone for when the unit needs to turn off. It then takes me 10 more seconds to get back to what I was doing. To turn the water off, I simply repeat. Total time invested to make water, 1 minute max. If you don't have that kind of time I have no idea how you do anything in this hobby. It certainly takes less time than driving to a store to purchase water and can be much more cost effective (especially if you calculate in the money you make per hour when working. If I am not spending time with my wife, then I figure out how much money I am wasting by not working.).

Second and most important- Confidence. I have 100% confidence that the water that is going into my tank has 0 TDS. Unless the store is willing to show me their TDS meter on their water every time I buy it, it isn't going into my tank. I don't know about the stores here, but there have been stores in Dallas that I know did not maintain their RO units to insure 0 TDS. We spend so much time and money on things in this hobby, this gives me a lot more peace at night that those things aren't being wasted. Plus, if I were ever to have an emergency at 2:00, I cannot count on a store to provide me water, but I can certainly count on being able to make it myself.

[wesreyn]

Plus, if I were ever to have an emergency at 2:00, I cannot count on a store to provide me water, but I can certainly count on being able to make it myself.

Great point Jason...

[renman303]

My main issue with RO is the waste of water and they generally only make ~20 gallons over a 24 hour period. Unless you have it circulating in a container already, so much for emergencies?...Whatever works best for you but, I don't feel that it's necessary.

[wesreyn]

My main issue with RO is the waste of water and they generally only make ~20 gallons over a 24 hour period. Unless you have it circulating in a container already, so much for emergencies?...Whatever works best for you but, I don't feel that it's necessary.

Ask don if it's necessary for emergencies.

[renman303]

Difference is Don lost over 200 gallons. Big difference.

I would have no place to store 300 gallons of water for my tank/sump. So, that is far outside of a "standard" emergency. None of these RO systems will make that amount of water quickly enough.

[JasonJones]

Valid points, but in an emergency you don't need to make that much water. Plus, most units make much more than 20g a day. RO does waste a lot of water, but if that is a main concern, save the waste waste water to use for other things, water the plants or something. But as long as you can get 0 TDS with DI alone, that is fine.

If you have a large tank, I bet that most of the vital corals and fish can be put into a much smaller container in case of an emergency. If you have a larger tank, you are likely to have some water free anyways. In an emergency situation, you are not concerned with refilling the entire tank immediately, you are concerned with providing just enough for everything to survive.

If my tank broke (20g), I have no doubt that I could fit all the corals and fish from my tank into 4 or 5 tupperware containers to house them for a few hours. This would take me 15-30 minutes to make the water tops, if I didn't already have some made or I couldn't save it from the tank. I think this is more than adequate.

Edited October 27, 2010 by JasonJones