RO or DI what is better

[DLANDINO]

I have a question for the chemistry experts. I do not own nor do I have the proper water pressure in my home for an ro/di unit. So, I have been purchasing my water from Walmart. I have stuck with RO water. The also sell DI water by Steam Distillation. Which of these two waters is best? Both measure 0 TDS on my meter. I have been battling green hair algae since upgrading my lighting 2 weeks ago and am wondering if a switch to DI would help. Thanks.

Dave

[jansenwrasse]

Both should be acceptable if they are testing 0 tds. If you were looking into a water system then Ro and Di together work well (assuming that the cartridges and the DI are well maintained).

Good luck!

[goodfortune]

I'd go with the DI.

Another option...if you have a Whole Foods nearby, you can go there to get DI water. That is were I buy mine; $0.39/Gallon.

HTH

[ILoveReefer]

There are small pumps out there made to increase water pressure so you can use a RO/DI unit's in low pressure areas.

[bertoni]

I agree that either is likely fine.

[DLANDINO]

Thanks for all of this input, I really appreciate it.

I have researched the booster pump option. Going this route bumps the cost of the unit up to by an additional 100$. All things considered though, I am paying .67 cents per gallon at Walmart and am buying 10 gallons per week for water change and top off. That is 384$ per year and roughly the same cost for a quality RO/DI unit. Uhmmmmm, what to do.


Dave

[kaskiles]

Don't forget the $50 per month savings on fitness gym costs. Carrying two 5 gallon jugs of water all around is good exercise. Particularly if you have some emergency and suddenly need to do a 50% water change.

Thanks, Kenneth.

[Duane867]

Buy an RO/DI unit. ;)

BUT if the unit you purchase has the DI cartridge mounted horizontally remove it and mount it vertically. It will last much longer and do its job more efficiently. ( pretty much all those Ebay jobs have them mounted horizontally so you will want to remount them vertically if you purchase one. Other wise they are good units though. )

[melev]

<a href=showthread.php?s=&postid=12668100#post12668100 target=_blank>Originally posted</a> by DLANDINO
Thanks for all of this input, I really appreciate it.

I have researched the booster pump option. Going this route bumps the cost of the unit up to by an additional 100$. All things considered though, I am paying .67 cents per gallon at Walmart and am buying 10 gallons per week for water change and top off. That is 384$ per year and roughly the same cost for a quality RO/DI unit. Uhmmmmm, what to do.


Dave

That seems much higher (almost double) than most of the systems I see sold online. Have you been checking the RC sponsors' sites?

[2thdeekay]

Have you looked into doing a simple DI unit without the RO? It doesn't need high pressure.

I was told by resin mfr (purolite?) all DI resin (even mixed bed) can be regenerated (if you know how). It's not hard, but there are chems involved. It would be a little easier if you started out with separate anion/cation bed resin.

If you don't want to DIY, the "ani kati system" might work for you. http://www.thefilterguys.biz/kati_ani_di-onizer.htm

[melev]

The Kati Ani system is a far better system to buying DI resin and trying to use that. DI won't last long with TDS levels above 10. It wouldn't take but mere gallons to wipe it out.

[2thdeekay]

Hi Melev! I really like your DIY info. I've greatly benefitted from your posts & website! I owe you thanks, then some.

I was under the impression that the Kati Ani System is a DI resin system, just a bigger volume of DI resin, that's all. They give you instructions on how to regenerate the resin.

I was told "all DI resin is regenerable" by the lead chemist at one of the manufacturers. I've seen mixed bed Purolite NRW-37 & Resintech MBD-30 regenerated and used over & over & over, but I could be wrong, as I haven't done it myself, and have never used the Kati-Ani.

But, you're right. A regular DI unit (for RO filters) wouldn't last long at all. They're too small. A larger volume of DI would be necessary, similar in size to the Kati Ani.

[melev]

I saw the Kati-Ani system at the last MACNA, and from what I've read in some threads, it works well. You definitely need to size those units to match the tank's needs.

You can definitely recharge DI resin. There is a pretty good DIY thread here on RC about how to do it, and I've got a full one gallon ziplock bag filled with used resin I've been saving for the past year or more, because I want to try it myself. :)

http://reefcentral.com/forums/showthread.php?s=&threadid=1144161&perpage=25&pagenumber=1
http://wichitaaquariumclub.com/forums/showthread.php?t=100

[2thdeekay]

Yup! That's exactly what I was thinking. I've been saving my used resin too! ;)

[2thdeekay]

Just FYI, the DI resin is MUCH CHEAPER from the Mfr, when you buy it by the cubic foot. Expecting my shipment soon.

Have a nice day Marc.

Mohri

[2thdeekay]

Sorry, double post