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gregzz4
01-14-2012, 12:15 AM
I'm finally making water with a 100gpd RODI unit
I flushed the pre-filters for about 20 mins, then flushed the RO for another 20 mins. It took forever to fill the DI
The TDS today is only 8ppm going in and 0ppm coming out of the RO, so I'm not wasting the DI. I have a 45g drum. There are no Chloramines in our water here.
My questions are;
-do I need a powerhead in the storage tank
-is there any point in a heater for the storage tank as it's in a heated room
-is 50/50 waste/clean water OK for the RO membrane
Any tips would be great thanks

coolhandgoose
01-14-2012, 12:27 AM
If you're just storing water you shouldn't need a power head, once you mix salt then use a power head for some good mixing. If you're getting50/50 water than that's awesome, I get like 80%waste to 20 good clean water.
What are you storing your water in?

hillegom
01-14-2012, 12:38 AM
Most RO systems have a 1:4 ratio. You are getting a 1:1.
What does your ro membrane's manufacturer suggest?

gregzz4
01-14-2012, 12:39 AM
After a bit of lookin', I probably should mod the original post, but I'll leave it for the membrane question.
It's a Vertex unit. With the waste water valve turned off, I'm still getting waste water. And I wouldn't be surprised if it's close to your 80/20
The storage is a cleaned out food industry 45g drum
I've heard of some people keeping powerheads in their storage tanks. Maybe that's for stagnant issues?
I did a taste test. Even removing 8ppm and the Chlorine, wow, what a difference in both taste and smell
The fishies are going to love this, as is my bottled-water buyin' wife :smile:

gregzz4
01-14-2012, 12:41 AM
Most RO systems have a 1:4 ratio. You are getting a 1:1.
What does your ro membrane's manufacturer suggest?

Sorry, the 50/50 was an original guesstimation, but that is way off now that I look down the drain with a flashlight.
They don't suggest. It's Vertex, and their documentation is horrible.
As stated above, with the waste water valve off, I'm probably getting at least 2 or 3:1 waste to clean. I gather the valve was built to alleviate any guessing

hillegom
01-14-2012, 01:14 AM
Usually the systems have a flow restrictor that is not adjustable, it is matched to your membrane's g/day output and usually gives you one gal of good to 4 gal of waste. I see yours has a valve so it seems you could dial in the ratio that you want.
I don't see your auto shutoff. It must be hidden behind the canisters?
You have done a fine plumbing job.

coolhandgoose
01-14-2012, 01:19 AM
Maybe someone else can chime in here as well but I don't think you should drink ro/di water, if you want you can dri k the water before it reaches the di phase. As long as the container isn't like an anti bacterial one then you should be fine.

gregzz4
01-14-2012, 01:40 AM
Usually the systems have a flow restrictor that is not adjustable, it is matched to your membrane's g/day output and usually gives you one gal of good to 4 gal of waste. I see yours has a valve so it seems you could dial in the ratio that you want.
I don't see your auto shutoff. It must be hidden behind the canisters?
You have done a fine plumbing job.
Thanks for the kind comment.
And thanks for taking the time to look at my build to note the plumbing
It's frankly a rats nest, but I did the best considering the space constraints
The check valve is behind/between the pre-filters, as well as the raw water TDS probe, and the auto shutoff is behind the RO canister. I don't get credit for the auto shutoff location as that is where Vertex placed it, and hard as I tried, I just could not locate it any better
Concerning the shutoff;
I'm a bit dissapointed. I installed the check valve and a float. I was expecting it to totally shutoff the water. It only cuts the new/clean water flow. So unless I plumbed it wrong, I guess I won't be leaving it running 24/7. Not that I plan on it, but it would have been nice to leave it fill itself after use and not worry about wasting any more water than necessary.

gregzz4
01-14-2012, 01:44 AM
Maybe someone else can chime in here as well but I don't think you should drink ro/di water, if you want you can dri k the water before it reaches the di phase. As long as the container isn't like an anti bacterial one then you should be fine.
Thanks for the heads up
Ya, I agree, drinking DI water is not so healthy. Besides the fact that we will not need to run the DI much with our clean city water, the plan is to only drink the RO water, and only use the DI for the fish if the raw water ever gets dirty enough, such as after a storm

gregzz4
01-14-2012, 01:46 AM
The container is not anti-bacterial. It's just a plain old, used food plant drum
It contained sugar for making chocolate and I washed the bleep out of it with direct hot water from our heater, then wiped 'er down and drilled away

hillegom
01-14-2012, 01:52 AM
The water should not continue flowing after the container is full. the auto shutoff should take care of that part. If it is not it is either defective or you have it plumbed wrong.
Three quarters of the way down the link, is a schematic (simple) that might help you. I do not have this brand of ro, just use it as a helper.

http://www.watergeneral.com/support/pdf/RO585.pdf
Take the 5th stage as if it was the DI then into the 45 gal drum
Delete the storage tank they have, unless you have one and attach it to the icemaker/drinking faucet
And I agree, if you are using this unit for drinking, tee off the drinking water before the DI

gregzz4
01-14-2012, 02:03 AM
Thanks for the link, I'll wander off now for a bit ...

gregzz4
01-14-2012, 02:36 AM
After consulting your linked schematic, and BRS's install video, I think I see the problem. I installed my check valve after the auto shutoff valve. I would have thought that it would work anywhere inline on the clean water line. But now I see that has no way of stopping the waste water {slaps forehead}
Thank you for the info.
I am off to tear it down. Wish me luck

gregzz4
01-14-2012, 03:30 AM
Thanks hillegom !
It takes a full 100 seconds, but it shuts off now. And thats at 60psi.
The system did not come with a check valve or float switch, so I can only blame me. But I must say even if it came with these items, with the instructions that were included, I probably could have pooched the install anyway.
I'm still proud of what I have done. I wanted the ability to monitor the TDS of the Raw, RO and DI water, use or not use the DI canister, and monitor both the Raw and Filtered water pressure.
Objective complete ... continue with suds :drinking:

hillegom
01-14-2012, 03:54 AM
Right on!
auto shut off is good

Myka
01-14-2012, 03:56 AM
The fishies are going to love this, as is my bottled-water buyin' wife :smile:

Lots of people suggest collecting water for drinking after the RO, but before the DI. The reef + drinking water systems on the market use a valve to bypass the DI resin for drinking water. I'm not totally sure why. I believe it is more taste than anything (I know I find DI water tastes funny), although I have heard things like DI water is ionicly aggressive and some impurities from the DI resin makes it into the water so is not healthy to drink, but I am not sure of the validity of those claims.

Btw, when it comes time to replace the RO membrane (years from now) replace it with a 75 gpd or 150 gpd RO membrane which is more efficient. Since you have REALLY low tds to begin with it really doesn't matter though. If you do change the membrane select a flow restrictor of the same rating.

As far as 1:1 output, I think you're quite alright with that considering you're only putting 8 ppm into the system to begin with. I have been using 1.5:1 for about 2000 gallons nows starting with 160-180 ppm and I'm not having any issues with the membrane clogging so far.

gregzz4
01-14-2012, 04:03 AM
Thanks Myka and I read up on drinking DI water. I see enough info to stay away from it.
For the membrane, I'll definately go with either a 75 or 150 with the next purchase, and I know what you mean about the restrictor. Too bad for me I didn't want to bother anyone before I bought the 100gpd unit I have now. It'll definately do the trick.
I could have bought the fancy shmancy Vertex automatic unit for what I've spent on what I have, but I have 2 gauges, 3 TDS meters and the ability to by-pass the DI.
5 of one and 6 and a half, or is that 7, of the other, oh, no wonder my budget is off

gregzz4
01-14-2012, 04:07 AM
So I got sidetracked with the repairs ...
A couple of my questions are, do I need to stir my storage tank ? Aerate it or heat it ? I'll gather heating it is a waste as it's in a warm room.

Myka
01-14-2012, 04:13 AM
The RO/DI doesn't need to be stirred, aerated, or heated. Whatever you end up doing with the water will make it a moot point. You will either put it into a salt mixing barrel where you will heat and mix (aerate) it, or you will put it in a tub for top off where it will just sit and get cold anyway. :D

Honestly, I would be ticked right off if I had 8 ppm going into the RO and having anything other than 1:1 water ratio. Most membranes suggest 4:1 which is for flushing the membrane as it runs to keep it from scaling, but with only 8 ppm going in, imo you don't have much to worry about. That RO membrane will last you probably 5+ years with that little load you're putting on it.

With 160-180 ppm my RO membranes last 2-3 years. I would rather replace my RO membrane once a year than waste that much water. So far, I haven't had an issue though...my membrane is lasting just fine at 1.5:1.

gregzz4
01-14-2012, 05:23 AM
Thanks Myka. And I'm not so concerned about the ratio as I was about harming the membrane with too much back pressure if I was to shut off the waste valve. Turns out I have no control over it anyway. Unfortunately, unless I change something, the valving on my system allows this much to bypass. So far though, looks like I'll get about 75gpd. I can live with that

PFoster
01-14-2012, 03:26 PM
I'm finally making water with a 100gpd RODI unit
My questions are;
-do I need a powerhead in the storage tank
-is there any point in a heater for the storage tank as it's in a heated room


I think you are in good hands with the other questions so I will add a bit to these.

You do not need a power head in your storage bin BUT if you add one (or better yet an air pump) if will bring up the pH of your fresh salt water before you add it to your system.
Test the pH of your freshly mixed sw, I can pretty much guarentee that the pH is low and this is done intentionally by the manufacturers as the lower pH allows the salt to mix faster.

As for a heater again its not required but it would help reduce the swings when you do your water changes.

The more stable your system is, the better your corals will look.

gregzz4
01-14-2012, 07:18 PM
Thanks P
I have heaters and powerheads for my ATO and New Saltwater holding tanks, so no concern there about variances.
About the pH in the storage drum... that rings a bell, but I don't recall what I read. I'll have to look around today about that as I want to know how that happens.

gregzz4
01-14-2012, 09:20 PM
I've been messin' around with the flush valve on the RO unit. I've found that I can totally shut off the waste water line, and then I get nearly 100gpd, based on some math.
I think I'll run it around 80gpd and flush it every couple of hours.
Otherwise, if I use the valve in it's normal position, I only get about 40gpd, with a lot of waste. No point wasting all that water with the incoming TDS @ only 7-8ppm.

hillegom
01-14-2012, 09:49 PM
Did you install a flow restrictor in the line? If the correct one is in there, you will get 100gpd with 400 gal waste. The flush valve should only be used to back flush the membrane, otherwise it should be shut off.
If you do not get 100gpd form a 100gpd membrane, then either your feed water pressure is too low, or the temp of incoming water is too cold.
I don't have a flush valve, the last membrane lasted 3 yrs. I have been debating whether I should instal one, but some co. speak against flushing.
So until I can research more, I won't backflush.

gregzz4
01-14-2012, 10:13 PM
Ya, I've been debating the whole idea of playing with the valve. With it completely closed, I'm not getting 100gpd.
I think I'll get a restrictor as this unit didn't come with one, neither inline nor in the output elbow.
Thanks again

hillegom
01-14-2012, 11:18 PM
Very unusual not to have a restrictor, it creates the proper backpressure so water gets fed through the membrane. I wonder if it already comes with one installed. Some restrictors are inside of the quarter inch black poly tube. It should be right at the connection where the black tube comes out of the ro membrane canister. It will look like this:
http://www.marinedepot.com/Flow_Restrictor_Flow_Restrictors_for_RO_DI_Water_F ilter_Systems-Captive_Purity-RO1210-FIRORAFR-vi.html
And is pushed into the black tube so only the shoulder is sticking out. Mine is coloured black and its hard to see unless youknow its there.

gregzz4
01-14-2012, 11:25 PM
It was definately missing. I checked all the packaging and the white tubing that came with this unit.
I just got back from J&L and there is now a 100gpd in the black line leaving the RO membrane.
I'll report back once I do some more math.
And once again, Thanks hillegom, you may have solved another issue for me :smile:
Down the road I'll change over to the inline style when I go with a 75GPD membrane. I've heard the 75s are more efficient.

Buckeye Field Supply
01-15-2012, 01:05 PM
A 75 gpd membrane with a proper flow restrictor will still produce apx. 4 parts waste water to 1 part purified water, so it's no more "efficient" in this regard.

What a 75 will do much better however, is clean the water. Here are some spec's for you (the 24 - 100 gpd membranes are Filmtec brand):

http://i224.photobucket.com/albums/dd293/BuckeyeFS/ROMembraneFactorySpecs-1.jpg

Russ

gregzz4
01-15-2012, 03:58 PM
Thanks for that Russ. I don't believe Vertex's claims of 98% rejection on the 100gpd I bought, but with 8ppm in and 0ppm out, guess it doesn't matter anyway. Makes me wonder if I'll ever need the DI.

mike31154
01-15-2012, 08:22 PM
On the other side of the coin, if your source TDS is consistently that low, you could simply run it straight through DI only, ditch the RO membrane altogether. Water production may be a lot quicker in that case, although not sure if contact time going thru DI is a factor, probably is. Don't necessarily recommend you do this, but I always like to look at things from a different angle. With an oversized cartridge full of DI media, or even a number of standard DI cartridges in series, you could probably get a good amount of 0 TDS water for your tank before the DI is depleted.

gregzz4
01-15-2012, 10:15 PM
Thanks for the thoughts Mike, but we'd like to drink the water too

hillegom
01-16-2012, 02:08 AM
T off before the DI for drinking. Tastes better.

gregzz4
01-16-2012, 05:05 AM
Besides the fact that RO tastes better than DI water, DI can cause serious health problems.
If you look at my build thread, you'll see my RO and DI are valved so I can bypass the DI.