RO/DI + Auto Top-Off Idea

[indyws6]

Greetings

I asked this question as part of another thread, but thought I would pull it out into a separate topic in the hopes of getting more feedback and suggestions. I ordered a Coralife PureFlo II 50gpd 4-Stage RO/DI unit that should be delivered tomorrow. For several reasons (the proximity of the incoming water line, ability to plumb to a drain, type of house construction, space constraints, etc.), I will be installing the RO/DI unit in my garage.
Here is the plan
1) Install RO/DI unit in garage.
2) Plumb RO/DI unit. There seems to be two schools of thought here - should I plumb it before the water softener, or after? Feeding softened water to the unit makes sense to me with the reasoning that the RO/DI unit will not have to "work" as hard, but maybe I am missing something
3) Build/install a DIY holding tank of about 40 gallons. Note: The brine tank for my water softener (a new one, of course) would make a great holding tank for RO water. It is the perfect size, it's rugged, it has a lid, it is already plumbed to accept the right size/style of flexible tubing and it has a built-in float valve. The downside is that it would cost $125 to buy one. I'm waffling on whether to build or buy - if you have a source for these that can save me $$$, I'm all ears...
4) Install a valve toward the bottom of the tank to make bucket-filling easier
Here's the area where I have the most questions and would really like some input and suggestions.
It would be relatively easy to route flexible tubing from the holding tank and up through the floor, either directly behind or in my stand, by running it through the crawlspace. What I think would be cool is if I could do this and include a small pump and float valve so that top-off water from the holding tank is delivered directly to the sump in my stand. Am I insane? Has anyone done this? Parts lists? Pictures? Suggestions?
Thanks in advance - as a newbie, I appreciate all of the help and will do what I can to return the favors in areas where I have some skills. (Let me know if you need any advice building a home network [Cisco Rocks!]

 

[weberian]

Automated is better, I agree. Be careful how far you try to pump through a little tiny 1/4-inch pex tubing, however. At that diameter, you have a ton of head loss - it might not make it there. If it's 15 or 20 feet away or more, I would guess you would have to up the tubing size, maybe use 1/2-inch glued pvc - it's cheap enough and easy to work with.
I've never tried to pump anything through 1/4-inch pex tubing, so I'm just spit-balling here - but I do know a thing or two about hydraulics.

 

[indyws6]

Weberian - Thanks for the information
You make a valid point. Total length would be in the 25-28 feet range, so it's possible that larger tubing may be needed. If I do this, I intend to use it only for top-off purposes (I'll fill buckets directly from the container for water changes, etc.), so I won't need a lot of volume or pressure.
I would prefer to use the smaller tubing and I think, even with a significant amount of head loss, it would be easy to generate enough volume to keep-up with evaporation. But, it may require a more expensive pump due to the length of the run and the pressure that would be generated. Fortunately, that tubing is relatively inexpensive, so it wouldn't be a heart-breaker if I built the system and then had to go to 1/2" PVC.
Anyone else???

Photos of systems used by others :help:

 

[weberian]

Do you have a pump you could test it with? Or borrow a fellow reefer's spare return pump and try it? Or bring 30-ft of pex to your LFS with an adapter fitting, and he could try it with a pump they have lying around.

 

[indyws6]

WEBERIAN - Thanks for the suggestions. My tank is not yet complet, so I could use my return pump (Mag 9.5) to test with. That should give me a pretty good idea of whether it is feasible for that distance using the smaller diameter tubing. My guess is that the distance will severely limit flow, but that it will suffice for an auto top-off situation.

 

[seannmelly]

i recently set up a unit in my basement. i have it going through about 25 ft. of 1/4" with no problem. its not auto top off but i just have it on a valve, when my sump needs filling i just turn the valve let it fill up then turn the valve off. simple and easy

 

[indyws6]

SEANNMELLY - Thanks for the information. Do you have any pics of your installation? What pump are you using?
I splurged and bought a new water softener brine tank today that I will use to store my RO water. It will hold 40-50 gallons (haven't done the math), has a float valve already installed and uses the appropriate size of tubing so I can avoid using adapters. It may take some time, but I think it will be worth the effort. What I envision:
1) RO/DI system outputs good water into the new tank and the included float switch will shut-off the unit when the tank is full
2) Install a short piece of 1/2" PVC and a ball valve towards the bottom of the tank for filling buckets
3) Install 1/4" tubing from the holding tank to the sump in the bottom of the stand
4) Install a float switch in my sump and use it to turn a pump on/off as needed to refill the sump - may do this manually to start and add the complexity of doing this automatically at a later date...

 

[seannmelly]

no pics at the moment. i just have the unit mounted on the wall in the basement with the 1/4" tubing running along the floor joce(sp) to where the tank is. up through the floor it goes into the sump, simple. thats about 25ft of the tubing. i use no pump except the house water pump. the house pressure pushes it through the ro and into the sump. i had to increase the water pressure from 40psi to 50psi. simple plan but work good. i have a t in the line incase i need to fill up buckets for water changes

 

[seannmelly]

ok heres some pics like i said simple setup but does the trick

 

[indyws6]

SEANNMELLY - Thanks for the information and hte pics - I appreciate it. I'll document my construction efforts in case anyone is interested.

 

[seannmelly]

your welcom glad i could help

 

[indyws6]

Greetings

Well, my RO/DI unit was delivered and I spent some time over the weekend working on the plumbing. I don't have the valve in the bottom of the storage tank yet (for bucket filling) nor do I have a line running from the storage tank to my aquarium for an auto top-off system, but I do have the RO/DI unit installed and working. :cheer: I was in the process of running the system to eliminate the first 10 gallons (according to the instructions) but went out of town Saturday and Sunday. I hope to be able to finish that this evening and then start filling my storage container and (eventually) my aquarium. I'm getting closer to actually having water in my tank

Here are some pics:
1) Coralife PureFlo II RO/DI Unit - 50 GPD
2) Detail photo of the Coralife unit and the included components
3) Photo of the plumbing work to "feed" the RO/DI system. The RO/DI is installed "after" the water softener so that softened water is used as the source - recommended approach according to a few of the water treatment businesses in the area. Looks like I got a little too close to the wall with the torch I'll have to do some touch-up painting...
4) Photo of completed installation. I will be building/installing a valve on the front of the storage container to allow for easy filling of buckets. The white tank is the brine tank for the softener...
Thoughts? Questions? Suggestions?

 

[weberian]

Cool. This may be nothing, but in the second to last picture, I see there may be a lot of torque put on the middle of the "H" that is formed by your tees and valves. Could you stabilize that assembly with a small piece of plywood with small half-circle clamps? That way when you turn those valves, the force is transferred to the larger plumbing pipe you have.
By the way, what is your house's plumbing pressure?

 

[renogaw]

Originally Posted by seannmelly
ok heres some pics like i said simple setup but does the trick
only thing i don't like about your setup is the brass Tee. won't the brass leach copper (especially since the water is hard metal starved) into your system?

 

[indyws6]

WEBERIAN - Thanks for the input. I don't think that there will be too much torque on the plumbing. The valves are good quality quarter-turn units that operate very smoothly and I would generally hold the pipe while turning them anyway. But, bracing the plumbing would be an easy thing to do and might avoid a future problem, so thanks for the suggestion. I have a city water supply, so I am guessing that the pressure is somewhere in the neighborhood of 60 psi, although I have never measured it.
RENOGAW - I honestly don't know for certain. It sounds like you have far more knowledge than I do when it comes to water chemistry. All of the plumbing in my house is copper, including the work I did to add the feed for the RO/DI unit. The exception, of course, is the valves, which are chrome-plated brass (there are 2 or 3 other all-brass valves in the mix before the water gets to the area you see in the photo). My gut feeling is that the amount of metal that would be leached into the system would be almost immeasurable with non lab-grade test kits. I may be wrong, though, so let me know if I am off-base on this. The flip side of that question would be "what options are there to fix the leaching problem if it exists"? Re-plumbing to eliminate copper pipe is impractical. Is there enough leaching for this to be a real problem? How would I know?
Thanks to all for the input and comments...

 

[weberian]

Originally Posted by indyws6
I have a city water supply, so I am guessing that the pressure is somewhere in the neighborhood of 60 psi, although I have never measured it.
My city pressure is around 100 psi, so I had to put a pressure regulator before the RO/DI filter. I forget the spec. on how much pressure the unit can handle. Congratulations - having your own RO filter is great.

 

[indyws6]

WEBERIAN - Thanks for the information...
I don't know the exact pressure, but I am certain that it is much less than the 100 psi you have. The rate at which the system was making RO water, based on the first 2-1/2 gallons, appeared to be slower than that needed to reach the 50 GPD rating of the unit. Although I didn't do the math to verify my assumptions. I suspect that it is entirely due to the incoming water pressure. I would likely have to do the opposite of what you did and BOOST the incoming pressure!
I don't think it will be a problem, though. I only need to have patience with the system while it generates enough water for my initial tank fill (90 gallons + the sump). There will not be the same demand for a large quantity of water after the initial fill - I'll only need to meet demand for top-off and water change uses. The storage container I purchased holds approximately 40+ gallons and has a float valve so that, once full, the output from the RO unit will be closed. As I drain water from the tank (filling buckets, etc.), the level will drop, the float valve will open and the system will refill the tank. If all goes according to plan, it should work quite well. I went to Menard's at lunch (hate that place, but no Home Depot here...) and bought the fittings and pieces necessary to build/install a 1" PVC spigot in the tank to make filling buckets easier.
The next step will be to build/install a system that will incorporate a float valve in the sump that triggers a demand pump to top-off the sump when the level drops. It sounds reasonable in concept, but may prove more time-consuming to implement (float valve, demand pump, plumbing between storage container and aquarium, possibly a relay so that the pump switch is low-voltage, etc.)

 

[weberian]

Sounds good to me.

Nice chattin' with ya.

 

[laxzach]

I have an auto top off system with a float valve and I think it is definitely possible for you to make one. The only problem you might face is the size pump you will need if you are moving water 30ft. Here are some pictures of my setup. I just installed it yesterday and I will be getting a new bucket and I will be hiding it. If you need to know where to get a good float valve send me an email at zrohlfing@gmail.com

 

[indyws6]

LAXZACH - Thanks for the information...
I don't see the pics - can you re-post? I'll send an email to the address provided tor details.
Thanks Again