RO/DI or Tap water?

[Orm Embar]

Another vote for RO/DI - if you ever develop algae problems (and you almost certainly will), not knowing how much your replacement water is contributing would be many more headaches in the long run.

I personally like SpectraPure (they claim that their extra membrane efficiency significantly prolongs your DI resin life and is cheaper in the long run), and have always had excellent performance and service. I strongly recommend a float valve (I have one in my refill bucket) compared to "I'll remember to check the bucket so it doesn't overflow" (used to get tons of spills).

If you want to save water, simply run the waste line from the RO into your washing machine. It's nearly identical to tap water except that it's been filtered through a sediment filter and a carbon block, with the waste water having slightly higher TDS (I think). I would think that it's better than tap for the washing machine. Heck, you could probably drink it and cook with it, too.

 

[Mark Derail]

RODI !!! See my previous posts on all the bad stuff that happened to my tank because I used tap.
TL;DR Never use tap

 

[FlyinBryan]

Yeah start out on the right foot. Rodi all the way! Tap would just add all kinds of unwanted nutrients and extra elements your tank doesn’t want or need like fluoride or even chlorine. If you’re here in Chicago you might get some anti-depressants or even Tylenol in your tank!
Like poster above said. This is not an inexpensive hobby. There are a lot of up front costs to doing it right. Strongly recommend an rodi unit. Ongoing filter costs as well.
Be sure you can afford the hobby.

 

[five.five-six]

This one time there was this guy in Flint Michigan who drank the tap water and died.

 

[mjlash22]

This one time there was this guy in Flint Michigan who drank the tap water and died.

Definitely would not want to use that tap water in a tank.

On another note. Another vote for RO/DI. My first salt water tank I did not use RO/DI system. Tap water with a conditioner. Worst experience of my life, and took me out of the hobby for a few years since I felt defeated. Did the research and started my second tank with a good knowledge base (and obviously RO/DI water).

In the end it's your decision, but as you can clearly see from this thread, 99% recommend a RO/DI system. I highly recommend the bulk reef supply units. I have the 4 stage 150GPD water saver plus model. I love it. Didn't need all the extra cartridges since my tap water is relatively low TDS.

 

[DLHDesign]

My LFS suggested me this one:

That's an RO unit that might go into a home to provide cleaner drinking water (thus the holding tank included with the unit - which would not come anywhere close to holding enough water for your tank). It's a step in the right direction, but if you're going to go in at all, you may as well get the right system for what you need.

The DI stage(s) add that extra "polish" to the water to get it down to the target 0 TDS. It helps to remove the last vestiges of things like phosphate, silica, nitrate, sulfate, aluminum, iron, calcium, etc. Some of these elements are thought to cause problems in reef tanks (silica could contribute to diatom blooms) while others are best to remove in order to better control their values (calcium is easier to control if it is 0 in your top-off water and base water used to make new saltwater).

I agree on the BRS suggestion. Whether you need a 4, 5, or 6 stage will depend upon your source water, however. Have you managed to get your hands on a water report for your area yet?

 

[andreasch]

Thank you guys. Ill definitely go to RODI water.

As i see most of you suggested me a BRS RODI system. Unfortunately i cannot get BRS in my country. So i want to ask, is there any difference whatever brand you get? The important thing isnt the membrane, the DI resin and the filters inside the system? As i understand whatever 5 stage RODI brand i get, the result will be more or less the same. Am i wrong to this?

ps. 1: Am not talking on the production rate.. Definitely is a difference between a 50GPD and a 150GPD system. Am referring only to the quality of the end water
ps. 2: @DLHDesign unfortunately i didnt manage to get a water report yet :/

 

[FlyinBryan]

Brand doesn’t matter as long as you can get replacement filter units. They’re all good, we’re just saying which ones we use. 4-6 stage and you should be fine.
It depends on how much water you need and how quickly. I just like getting it done quickly plus I’m recirculating some of the water making it more efficient.

 

[DLHDesign]

So i want to ask, is there any difference whatever brand you get?

In terms of the hardware; likely not much difference. So long as stuff doesn't leak, it'll do the job. The key will be to ensure you are able to measure the effectiveness of the system - which is most easily done with at least one TDS meter (though three is often best and will pay for themselves in the long-run).
In terms of the filters; yes - it does matter. For the RO membranes, most of the things on the market are made by DOW and are all pretty much the same high quality. Any other manufacturers may also be high quality, but you would want to check their "rejection rate" and pressure requirements (which will determine whether you need a booster pump or not).
In terms of the DI resin; yes - it does matter. Different types of resin do different things, so while it's unlikely that you would buy anything that isn't just "mixed", that's something to look for. Different manufacturers also likely have different qualities of resin, but I doubt that it will matter much.

If you can't find a water report, I would suggest going with at least a 5-stage unit. The 5th stage is a second carbon block, which could potentially make a significant difference in the end quality, but won't really cost you very much (either up-front or in terms of filter costs over the life of the system). The mounting brackets for 4-stage versus 5-stage are also often different, which makes upgrading from 4 to 5 more difficult (not impossible, however). Adding a 6th stage (a second DI canister) is often very easy to do after-the-fact, so you could save some money initially until you know you need it. (Note that a 6th stage can help you get the most out of your DI resin, so it will likely pay for itself in the long run.)

 

[cloak]

I apologize for not reading through the entire thread, but FWIW I've used tap water for my reef tanks for the past 18 years or so and have never had any serious problems. Sometime around 2009 I had my LFS test the TDS and it was 46. I just had it tested again a few months ago and it was 159. (whatever that means)
On a side note; I did purchase a 4 stage RO/DI unit from Bulk Reef Supply this last fall and so far I haven't noticed any difference yet. Hmm...

http://www.advancedaquarist.com/2004/1/chemistry

 

[DLHDesign]

@cloak - It may be worth reading through some of the thread (and their links - which includes the one you shared again; always good to reinforce the good stuff <grin>). It's quite possible to have a reef tank that runs off tap water in some areas - but even in the best of them, a reefer is more likely to have issues when not using RO/DI water than when they do.

Unless you do a tank tear-down and reboot (new sand and rocks), it's unlikely that you'll see any short-term benefits from your switch to RO/DI (aside from your TDS not increasing further, of course). The challenge is that the "stuff" is in your tank already, and water changes aren't going to remove it all. They'll help, but it will take time as you're only able to take a fraction of the water out (eg; you can't divide-by-half and get to zero). Note that I'm not in any way suggesting a tear-down for you; obviously your tank is able to handle things as they are!