Does everyone just end up buying an RODI system eventually??

[MJ in Boise]

I agree but I don't know many situations where temprature will be a factor.
I would say few if any would use them in a close to freezing envirnment.
More in hotter environments.

-3% per 1 degree F below 77F. Examples: 60F=-30%, 50F=-50% production.

 

[Brew12]

[

I'd still be concerned you might be burning through resin much quicker than you normally would be, have you checked your TDS after the membrane before your DI atall? Maybe you have rather low TDS to begin with and this particular system works well enough. The cost of water is pennies compared to the cost of DI resin. So I'd hate to see it cost you more in the long run

That was my thought, too. I'd much rather have the RO filter do the bulk of the work instead of relying on the DI resin. My RO unit drops me from 60tds to 2tds with the DI resin doing the remainder and I still have to change it out at least 2 times a year.

 

[JoshH]

[

That was my thought, too. I'd much rather have the RO filter do the bulk of the work instead of relying on the DI resin. My RO unit drops me from 60tds to 2tds with the DI resin doing the remainder and I still have to change it out at least 2 times a year.

Man, I've got to shoot you a Spectrapure membrane lol

 

[Bleigh]

Yes. I started with the RODI buddy and upgraded to a full water system.

 

[Buckeye Hydro Verified Sponsor]

Then why don't all rodi system use tighter flow restrictors in the 1st place? I would think there must be a reason why the current flow restrictor is in place?

Great question.

In the absence of lab data about your water quality and water temperature and water pressure, responsible vendors will provide a flow restrictor that yields a 3:1 to 5:1 ratio so that you get a reasonable life out of your RO membrane. That said, sometimes we have customers provide some of the data I mentioned above, and we can provide a tighter (less waste) flow restrictor.

This is one reason we do not like that reefers refer to concentrate as "waste water." It really isn't wasted - it does the important job of flushing off the surface of the membrane.

 

[Buckeye Hydro Verified Sponsor]

i have looked into CO2 issues with ground water. i wonder if ground water to holding tank (allow circulation turbulence to off gas the CO2) after some dwell time in the holding tank, pumped through a RODI would eliminate the premature aging of the DI resin this is discussed on this site.

Yes - you can do that. Put a airstone in it that pumps in fresh air.

 

[chipmunkofdoom2]

Because the membrane will not last like it was designed but that comes at the cost of more water usage to run it. If getting the least amount of waste water is your main concern restrict the waste line more.

I wish I had more than one like to give to this. An undersized flow restrictor reduces the "waste water" from your system by starving your membrane of the brine flow it needs, ultimately killing it early. Adding a second membrane does the exact same thing, it just costs more and uses more parts. The only real reason you'd want a dual membrane setup is if you don't care about killing your membranes and you actually need to produce 150g of permeate per day.

 

[KStatefan]

I wish I had more than one like to give to this. An undersized flow restrictor reduces the "waste water" from your system by starving your membrane of the brine flow it needs, ultimately killing it early. Adding a second membrane does the exact same thing, it just costs more and uses more parts. The only real reason you'd want a dual membrane setup is if you don't care about killing your membranes and you actually need to produce 150g of permeate per day.

I think there are some situations (expensive water, very low source TDS) that is would be a good choice.
It will also consume DI resin faster as the second membrane is not as efficient and starts with higher TDS water.

 

[chipmunkofdoom2]

@magicwhistle
You can drink the RODI water but it is technically not good for you. By removing almost everything from the water in an attempt to get 0 TDS, you make the water unstable. It then pulls minerals from its surrounding environment. When you drink it, it is removing minerals from your body, making it "unhealthy"
I'm no expert, but I have heard you can mitigate this by leaving the container open and it will pull minerals from the air or you can add a teaspoon or two of brine (waste) water to it

Citation needed. I've never once seen any solid data to support this argument. Let's calculate exactly what you're missing out on by drinking RO water as opposed to tap water. The average TDS of US tap water varies, but the EPA specifies a max level of 500 mg/L in their secondary standards literature. Let's assume that you have 500 ppm TDS in your tap water, and that you actually drink your tap water (lots of people don't). The average person needs to drink about 3L of water per day. If your tap water is 500 mg/L, you're consuming 1,500 mg of solids per day from your water. So, by consuming deionized water instead of tap water, you're missing out on 1.5 grams of Ca, Mg, Na and other ions commonly present in tap water. So the argument is that by missing out on 1.5 grams of Mg and Ca from tap water, your body is going to be robbed of minerals? I don't buy it.

This argument also doesn't make sense when you consider that your stomach is primarily full of hydrochloric acid, among other things. Since HCl is many orders of magnitude more acidic than purified water, shouldn't you be concerned about the vat of acid sitting inside your body?*

* - rhetorical. No, you should not. Your pancreas produces bicarbonate to neutralize any stomach acid that makes its way out of the stomach. This bicarbonate and other foods you eat will be more than enough to replace the 1.5 grams of solids you're "missing" because you're drinking purified water.

 

[Dr. Dendrostein]

I'd still be concerned you might be burning through resin much quicker than you normally would be, have you checked your TDS after the membrane before your DI atall? Maybe you have rather low TDS to begin with and this particular system works well enough. The cost of water is pennies compared to the cost of DI resin. So I'd hate to see it cost you more in the long run

My system only 90 gallon volume, so the RO water I make, not much. Next time I need to check TDS

 

[magicwhistle]

Citation needed. I've never once seen any solid data to support this argument. Let's calculate exactly what you're missing out on by drinking RO water as opposed to tap water. The average TDS of US tap water varies, but the EPA specifies a max level of 500 mg/L in their secondary standards literature. Let's assume that you have 500 ppm TDS in your tap water, and that you actually drink your tap water (lots of people don't). The average person needs to drink about 3L of water per day. If your tap water is 500 mg/L, you're consuming 1,500 mg of solids per day from your water. So, by consuming deionized water instead of tap water, you're missing out on 1.5 grams of Ca, Mg, Na and other ions commonly present in tap water. So the argument is that by missing out on 1.5 grams of Mg and Ca from tap water, your body is going to be robbed of minerals? I don't buy it.

This argument also doesn't make sense when you consider that your stomach is primarily full of hydrochloric acid, among other things. Since HCl is many orders of magnitude more acidic than purified water, shouldn't you be concerned about the vat of acid sitting inside your body?*

* - rhetorical. No, you should not. Your pancreas produces bicarbonate to neutralize any stomach acid that makes its way out of the stomach. This bicarbonate and other foods you eat will be more than enough to replace the 1.5 grams of solids you're "missing" because you're drinking purified water.

Not that I agree with what he’s saying but he isn’t saying that you’ll miss out on the electrolytes and stuff in tap water.

more that them missing from the water will upset the osmotic pressure of each of the minerals and you won’t be able to have homeostasis anymore. So the cells will lose say their calcium and magnesium.

This probably can happen. But I’d imagine you need to drink an insane amount really quickly OR be on a fast while only drinking RODI water. And for it to have noticeable effects you’d have to do these things pretty regularly.

 

[K7BMG]

Hey everyone, don't want to be a jerk here but take the conversation elsewhere.
It is not polite to highjack a persons thread with stuff or arguments not related to the OP's question.

You don't want this to happen to your posts and I am positive the OP does not as well.

Sorry but you all are being rude here.

The OP want's to know about buying or not buying a RO/DI.
If so what is the recommendation on a system.

 

[JoshH]

Pot..... meet Kettle?

 

[K7BMG]

Pot..... meet Kettle?

amen and touché. lol.

 

[JoshH]

amen and touché. lol.

I do agree that the conversation has certainly veered off course, just having a little fun. I will add that in the conversation veering off course SOME valuable information has been shared one can learn from. Certainly not everything that has been shared though...

To answer the OP's original question, I believe almost all of us end up getting our own RODI filters. They are definitely worth it and can pay for themselves in a relatively short period of time. I myself am a fan of Spectrapure, aside from there no free shipping lol

I run a Dual membrane (In Series, don't hold it against me ;Facepalm ) 180 GPD system and LOVE it.

 

[K7BMG]

Ok so more kettle meeting.
Yes some, but very little information was learned.
I like the input on the membranes and to run two in series or not.
Something to consider when purchasing a unit.
I have read things and have watched a video or two on the subject and I had come to the conclusion that two units in series works.

But the drinking of RO/DI water and its effects on the human body well that's a bit suspect for this thread. Sorry folks I feel has no place here anyway.
There are many threads on that subject and yet I can't see why.
I don't know if anyone who would be running a line to their sinks for personal use.

But yes I feel all saltwater aquarium owners who intend to have corals in the aquarium should have a solid RO/DI unit.
IMO this includes all sources of water, city, well, or whatever else is out there.

If its going to be a fish only aquarium then yes I see no point in having a RO/DI.
I was shocked to see Brew12 had a opposing view, but did he really? As I read and tap finger on chin. lol.

 

[magicwhistle]

Of course it has a place here. The conversation is more than just the title eh?

Their issue is with using the drinking water filtration system for the fish tank. If they got an entirely new filtration system it’s conceivable they’ll use it for drinking water too. I know I did when I got my unit.

If anything your guys posts haven’t really been constructive to helping OP. They’re having issues with water quality and while they haven’t answered my questions from before I’m doubtful that their issues are related to filtered water quality issues. Something else is going on. While you guys are going off about yes buy this filter and that filter accessory ... but it’s not gonna help the OPs misconception that their pH should be 0 or that they are having climbing ammonia and nitrites in a tank that was seemingly cycled months ago.

 

[vetteguy53081]

I used to run to walmart and fill 2-3 five gallon jugs and leave happy. never realized the quality and convenience of making my own water and with ease. It paid for itself from running to walmart in 5 months.

 

[FastandCurious]

Wait what exactly is the problem? Which parameters are you trying to get to 0? Where are you trying to get them to 0? In the tank or freshly mixed saltwater or from the freshwater source?

You said your pH isn’t getting down to 0 but it shouldn’t be.

Your tap water has ammonia and nitrites in it? Even after filtering it as your drinking water?

I’m assuming at that point you’re talking about in the actual tank.

Has this tank been cycled?

Edit: I’m not against getting a rodi system but just want to clear up any confusion you might be having. If you already have a filtration setup that your LFS says will work it might not be necessary to get a RODI system and from what you’ve posted so far I don’t see anything about why your freshwater isn’t good enough. What’s the TDS of your filtered water?

I started with a 4 stage RODI and loved it. Upgraded to a 5 stage with booster pump, made a tremendous difference in the time to generate the water I required. Can't imagine not having one. There is a difference in the drinking water and RODI for fish tanks. It is my understanding you should not be drinking the water our of the RODI unit.

Yes I know they are different. The filtration system I have now I guess is just not enough to clean the water for the tank. I think I'm going to just end up investing in one. Make my life a little easier lol

 

[FastandCurious]

And of course get your supplies from Buckeye as well!

Lol thanks