Ro Vs Rodi

[D.J.]

explain the difference........i can great deal on an RO unit.....but its RO only.....i know i can get a DI add on from bulk reef supply.....but is it really needed right away?

ive always been confused on the whole ro and rodi systems..........

im using regulare RO water in my tank right now....WALMART.......SHUT UP........lol..........just because the place im in now isnt filtered......but even before i was just using RO water......the place we was in had an RO filter on the well pump......and no issues in my tanks after a year of using that......

[quader94]

ro has a higher tds, when i run just the ro part, my tds is 7. but when i run it though the di too, its 0

[D.J.]

i figured it would have something to do with the TDS of the water.....

BUT like i said ive been runnin RO only water for a year in my new system and no issues.......not sure if im lucky or what......

[jenglish]

A lot of it depends on your source water. if you started with 500 TDS and a 98% rejection you would still have 10 TDS. If you used a lot of top off and kept very sensitive organisms that may be a huge problem... it may not. Of course pure-er (is that a word?) is better, but there are still people out there that maintain successful reefs with tap water. So who knows if it will be a big deal for your tank.

[D.J.]

ya i dont have alot of SENSATIVE things in my tank......mainly softies witha few sps/lps corals.....

i think the 2 most sensative things i have is my purple crocea and pink xenia.......

[tangmang23]

i agree. The more pure the water, the better your odds of maintaining a "trouble free" system will be. I was using RO only for a short amount of time, and I doubt age of the tank had anything to do with it, but after I added DI, things seem to look that much better. If I were in your shoes, id just get what you can now, and just plan to add later. I dont for see a huge issue off the bat.

[hansmatt]

yeah, I ran Festival RO for a year or so...I was nuts running back and forth with 3-4 5 gallon jugs, plus another dozen gallons every week or so...

I don't know if it was due to the water or not, but I had hair algae like crazy, drove me nuts and then some, during most of that time. I put in my own RODI and things turned around. You probably don't NEED the DI, but in the end, you put more water into the tank than anything else...it is the single most important ingredient to a good tank.

[D.J.]

the only good thing about the walmart ro water is kim and i both work there so we can just bring our 5g jusgs with us and fill them after work.....

i dont go thru alot of water.....about 5g every 5 days.....but its still more than i wish i was goin thru....

im lookin into ro and rodi filters now.....so hoepfully i can find somethingi can afford....but gota get tires and an alignment on kims truck ASAP so im gona have to deal with walmart ro for alil while...

[schneijt]

If you're going to get RO water from Wal-Mart or a grocery store or whatever, you should really have a TDS meter to see what you're putting in your tank and making sure it's actually "good" water. I've read some stories online of people who have discovered that their RO water from the grocery store had a TDS equal to their tap water, etc... Just because they say it's RO water or distilled or whatever doesn't necessarily mean it's ultra-pure water.

As far as the DI, some people don't use one and have amazing reefs. It's really about your source water. If you have high silicates or something like that, you really want a high quality DI resin to make sure you remove any residuals that might get past your RO membrane. Think of DI as being kind of like boosting the octane of your gas. Regular unleaded gets you down the road just as well, but the Premium Unleaded gives you that piece of mind that you're putting the best possible fuel into your gas tank.

At the end of the day, nothing ruins your water quality like starting off with bad freshwater to mix your salt with. Since the ultimate goal of ours is to achieve and maintain the best water quality possible, I really think everyone should own his/her own RO/DI unit and a TDS meter. (And it also helps if you educate yourself about your system and know how to maintain it so it's always making "perfect" water.) If you control the source water by making it yourself before you mix salt into it, you always know precisely what's going into your tank. Not to mention, it saves you time, money, and the hassle of lugging jugs of water around town.

Ok, I'm off my soap box.
Joe

[D.J.]

whats with all the waste water? is it just water taht dont get filtered or what exactlly is it? just seems like a big waste if you dumpin as much water as your filtering.....

ive seen some NO WASTE ro systems but they are kinda spendy.....

lookin on bulk reef and marine depot and fosters doin some comparisons.........maybe ill come back from f&s with one....

the ones that menards has seems to be a bit much for something that you have to add to to get rodi....imo.....since you can get a 3 stage rodi for around the price of the menards ro systems.....so i think im gona stay away from that......

i have yet to find a TDS meter......when i found one at walgreens...i was told on here that they really arent needed.....and now im leaning towards needing one with this ro issue and now i cant find one..............shoulda bought it when i seen it.....oh well.........

[schneijt]

I'm not sure who told you you didn't need a TDS meter, because that just seems absurd to me. It'd be like someone saying you don't need a test kit for something... If you want to know the purity of your RO water, you need the TDS meter. They're pretty cheap online, but I know your funds are a bit tight lately.

Waste water is water that doesn't get filtered, yes. For most RO systems, you want four parts waste water for every one part of purified water. Lots of people plumb the waste line to their washing machine or something of that sort, in order to preserve water. Personally, I just run my waste water line from the RO unit to the floor drain in our basement. The reason that waste water is a good thing is that it transports the particles that make up your TDS reading away from the RO membrane. Without waste water, the membrane would clog quickly and have almost no lifespan. I don't know how the "zero waste" systems do it, but I'm sure someone out there can explain it. But, waste water isn't such a bad thing, unless you have one of these miraculous "no waste" RO systems.

As far as where to buy it, BRS or BFS (Buckeye Field Supply) or DFS or PurelyH2O.com etc... Definitely buy it from a place that specializes in RO/DI systems for reef use. They know how picky we are when it comes to the final product, so they make sure to sell us only the best membranes, DI resin, etc when you go through one of the above retailers.

-Joe

[hansmatt]

agreed...BRS, firewaterice, spectrapure, buckeye are all common reef systems, even Melev's reef has RODI by reefers for reefers. I'll keep my spectrapure, or buy another. They do have a super efficient system, that has less waste than any other system, but it's super spendy and only worth it when you have very high water fees, like Arizona, parts of the mountain west, NYC etc. If you have well water, you're golden...still not bad on city water with 246tds going in and 0 coming out. Most better systems have tds meters built in...mine has an incoming and outgoing.

[schneijt]

Matt, that brings up another good reason to have a TDS meter. TDS meters allow you to evaluate the performance of your RO membrane. You want to know the TDS of the water right before the membrane, and also the TDS of the water right as it exits the membrane. This way you can calculate your membrane's rejection rate. (For example, my TDS is roughly 110 after the pre-filter and carbon clock. After it comes out of the membrane, it's TDS is 2. This means that my 98% rejection rate membrane is functioning properly, since it's rejecting at least 98% of the TDS from my water.)

I prefer to have a handheld TDS and also an in-line TDS meter that hooks into my RO system so that at a touch of a button I can know the TDS before and after the membrane. That makes my life much easier than having to use a handheld TDS meter to measure pre- and post-membrane.

-Joe