RODI water vs tap water

[linbeg]

I know that most individuals choose to use RODI over tap water, because of it's impurities such as high phosphates and nitrates and other impurities which can eventually lead to unwanted growth in the aquarium. However, is the phosphates and nitrates in tap water the main reason why some people choose to RODI over dechlorinated tap water? If it is, would it be plausible to use dechlorinated tap water, add salt, then add chaetomorpha and let it stay for a week or so. Wouldn't the chaetomorpha absorb the phosphates and nitrates, thereby making the water suitable for saltwater aquarium? Or am I just thinking of it wrong?

OR if topping off for freshwater, using a phosphate media?

Edited February 5, 2011 by linbeg

[bioload]

I know that most individuals choose to use RODI over tap water, because of it's impurities such as high phosphates and nitrates and other impurities which can eventually lead to unwanted growth in the aquarium. However, is the phosphates and nitrates in tap water the main reason why some people choose to RODI over dechlorinated tap water? If it is, would it be plausible to use dechlorinated tap water, add salt, then add chaetomorpha and let it stay for a week or so. Wouldn't the chaetomorpha absorb the phosphates and nitrates, thereby making the water suitable for saltwater aquarium? Or am I just thinking of it wrong?

 

IMO theres no way of getting around the necessity of using at least RO water.Most tap water is a "chemical soup" and just won't work long term. There are a lucky few that have very pure tap water but thats few and far between.

[19jeffro83]

Do a search. This has been discussed many time. Ro/di is the best followed by distilled. Don't use tap you'll regret it. Trust me...

[OClownsandNanos]

Main (not all) problems with tap are: phosphates, nitrates, silicates, and heavy metals. Dechlorinated tap would probably work okay for a fish-only saltwater tank, but you are really taking a risk with invertebrates by using unfiltered tap. Reef tanks are ultimately expensive propositions from the equipment to the animals and LR stocked within them - doesn't make sense to take such a large risk on your investment by using unfiltered tap. Average case you get a load of algae blooms difficult to control, worst case it causes a tank crash.

 

And it's not just a choice between RO/DI or tap. You could do RO or distilled also. RO/DI is ideal; tap water is the very worst you can opt for.

[jeffblly]

Dont do it if you want to grow corals. Your forgetting all the other chemicals that are in tapwater. Look at your city water report.

[linbeg]

i heard distilled is bad tho?because it interferes with something ionic in a saltwater tank. Is that true?

[sean151]

i heard distilled is bad tho?because it interferes with something ionic in a saltwater tank. Is that true?

 

No, I and many others, have been using almost elusively distilled for almost a year without issue. Just remember RO/DI>Disitilled>RO almost no other option outside that for long-term success.

[diablovt750]

RO water is .50 a gallon at walmart. It is so cheap that why wouldnt you use it? It just seems funny to me that you would declorinate tap water and let it sit for a week with cheato before using it when you can just open the bottle and pour. It would suck having to prepare for a water change a week in advance! LOL

[nebthet]

From my experience... and you can see the results of using treated tap water in my 57g tank thread, RO or RO/DI water is a lot better to use. Not only from the standpoint of using algae, but there are a lot of other impurities in tapwater that we don't take into consideration when using it.

 

While I was able to get some growth out of corals and decent coloration, the growth of the corals was not there and the colors I did get were dull at best. I also had the algae issues.. huge algae issues, for a long time.

 

Once I started switching over to RO water, via water changes and top offs, and added a couple turbo snails to help with the algae I began to see noteable inprovements. Faster growth in all corals in addition to much thicker skeletons. Better color and my skimmer started to work properly.

 

Here is my tank in Oct 12, 2010. Before the switch over when I still used tapwater.

 

Nov. 19th, 2010: Two weeks into using RO water for water change.

 

Dec.18th, 2010:

 

Now, all but one of my sps are happier than they have ever been and growing has really taken off. Especially my encrusting montiporas.

My acans are still really happy and growing like crazy too.

I have a yuma that is reaching 4inches in diameter and am hoping to heck it decides to split.

Both sebae and rbt anemones are happier and growing larger day by day.

Xenia has decided to have a growth explosion on me and I have to frag it all the time.

Glass is easier to keep clean, less algae, less cyano, equiptment works better.

 

So, from my experience, while tap water can be used for salt water tanks.. and I have seen some of them that I thought were ro/di water and they were actually tap, it is not recommended unless you have your city or well water tested regularly to determine the tds level and what is actually in it.. City water fluctuates all the time. ie.. heavy rain = more bleaching agent, so much so you can smell and taste it in our local waters.. I avoided water changes at these times.

 

You will need to do a lot more tank maintenance to keep the algae at bay, which means, no going away for two or three days at a time because the film gets on the glass and is a pain to get off, even now I can't remove it. Use lots of dechlorinator and dechloriminator, when using tapwater, also let it set for 48hours before using it and syphon out the last couple of inches before use as heavy metals, etc will settle on the bottom of the bucket and you don't want those in your tank. You will also want to use lots of chemipure elite and phosguard or Phosban to help with phosphate removal and switch those out every month.

 

With the switch over from my tank, it went from people saying , "That's nice" to "God, that's gorgeous".

[linbeg]

No, I and many others, have been using almost elusively distilled for almost a year without issue. Just remember RO/DI>Disitilled>RO almost no other option outside that for long-term success.

 

Wait, the if Distilled Water is better than RO water. Do lfs sell RO/DI water, or is it just RO water? If not, then i should might as well get Distilled water right?

[linbeg]

No, I and many others, have been using almost elusively distilled for almost a year without issue. Just remember RO/DI>Disitilled>RO almost no other option outside that for long-term success.

 

Wait, the if Distilled Water is better than RO water. Do lfs sell RO/DI water, or is it just RO water? If not, then i should might as well get Distilled water right?

And is one brand of Distilled water better than another? or are they all uniformly the same?

Edited February 10, 2011 by linbeg

[Alexraptor]

Tap Water = Potential Tank Crash waiting to happen a few years down the line.

[paneubert]

Wait, the if Distilled Water is better than RO water. Do lfs sell RO/DI water, or is it just RO water? If not, then i should might as well get Distilled water right?

 

Most LFS are just doing RO....which is why it is sometimes cheaper to use the Wal-Mart machine if the TDS on it is low. The assumption is that Wal-Mart is not as good at keeping the RO clean and that the LFS is.....which is not always how it works.

 

Experience varies depending on how nice your LFS is and how crappy your Wal-Mart is.

[sean151]

Wait, the if Distilled Water is better than RO water. Do lfs sell RO/DI water, or is it just RO water? If not, then i should might as well get Distilled water right?

And is one brand of Distilled water better than another? or are they all uniformly the same?

It has to do with the way of purification. Some LFS sell RO and some RO/DI, just ask or better yet buy a TDS meter and test it in front of them. One of the LFS within an hour from my parent's house in Auburn has a 55 gallon tub of RO/DI and another of saltwater to eliminate TDS creep, small things to look at and remember when buying from a LFS. If you get a TDS tester and the RO or even RO/DI tests at an "unacceptable range" and distilled from the grocery store is not much more expensive then I would think about going that way.

 

I find it cheaper and easier to get distilled from the grocery store, but do get RO also as distilled sells out fast. Just find what works for you, if the LFS is around 50 cents or so a gallon for RO or RO/DI then either their water will be great to use or I would recommend getting your own RO/DI unit to save on cost and to know your water is safe for sure.

 

Most LFS are just doing RO....which is why it is sometimes cheaper to use the Wal-Mart machine if the TDS on it is low. The assumption is that Wal-Mart is not as good at keeping the RO clean and that the LFS is.....which is not always how it works.

 

Experience varies depending on how nice your LFS is and how crappy your Wal-Mart is.

+1 and always be proactive about making sure water quality is there.

[linbeg]

sean151, so if i get a TDS it should read 0 on the RO or distilled water right? but what exactly is the difference between RO and distilled water? RO is passed through a membrane, in order to eliminate impurities but isn't distilled water also pure? which is the same thing?or no?

[sean151]

sean151, so if i get a TDS it should read 0 on the RO or distilled water right? but what exactly is the difference between RO and distilled water? RO is passed through a membrane, in order to eliminate impurities but isn't distilled water also pure? which is the same thing?or no?

RO can be 0TDS but is more commonly 90 some odd percent lower than the tap water going in, some people get 0 and some a lot more. The DI phase is what brings down the last of the TDS to 0. Distilled is a different process and just happens to fit between the two "on average". There are a few studies done on comparing bottled distilled to bottled RO water with distilled being better, but in the end it's close enough that if you are buying at the store it won't matter. Any LFS worth buying water should be willing to test the TDS of the water in front of you, as they should be testing it themselves every so often. If they don't have a TDS meter be the proactive reefer and get your own as down the road you will want it anyways and you might as well test their water before you might move to your own.

Sidenote: I do not have my own TDS meter as I only have a 5.5 and am away at college, but if I suspected water problems from the source I wouldn't hesitate to get one.

[linbeg]

RO can be 0TDS but is more commonly 90 some odd percent lower than the tap water going in, some people get 0 and some a lot more. The DI phase is what brings down the last of the TDS to 0. Distilled is a different process and just happens to fit between the two "on average". There are a few studies done on comparing bottled distilled to bottled RO water with distilled being better, but in the end it's close enough that if you are buying at the store it won't matter. Any LFS worth buying water should be willing to test the TDS of the water in front of you, as they should be testing it themselves every so often. If they don't have a TDS meter be the proactive reefer and get your own as down the road you will want it anyways and you might as well test their water before you might move to your own.

Sidenote: I do not have my own TDS meter as I only have a 5.5 and am away at college, but if I suspected water problems from the source I wouldn't hesitate to get one.

 

Since you said 90% of the TDS, what would the content of 10% left? Chlorine?phosphates?nitrates? or other minerals? And is it safe to use this as my primary source of water for my aquarium?

[Mitch619]

WHY ARE WE HAVING RODI CONVERSATIONS?

 

Sorry for the caps, it just makes me mad!

 

Use the search feature. you noobs will see that tap water sucks. And that RODI is the way to go.

[sean151]

Since you said 90% of the TDS, what would the content of 10% left? Chlorine?phosphates?nitrates? or other minerals? And is it safe to use this as my primary source of water for my aquarium?

Chlorine should be taken aware by the carbon in the RO system. But it's virtually always more than 90% is taken away. Sometimes 97-100%, but as stated above the best choice is ALWAYS RO/DI as it's as clean as you will get in this hobby. It's the first real buy for many reefers after they started their tank and I should be pushing for it more than I have been informing. With your own system you have full control of your water quality and the easiest access to it. It will pay itself off money wise by up to two years and headaches/stress that accompany water quality problems will be minimized(intangible benefit). Sorry for the conflicting info, you can start with water from the LFS, but you will almost always move over to home-brewed RO/DI. Check out the "Water Quality" section of N-R and you can learn tons in a few days.

[RK_tek]

One trip to the LFS to haul buckets of water home changed my mind about spending the money on an RO/DI. I got a spectrapure on sale and it will have paid for itself monetarily in just over a year. I also like having the peace of mind that I can always have water if a tank starts to crash or something. Coming home at midnight from a 3 day trip to find your parameters through the roof from dead livestock and being able to do an immediate water change to save everything else is a good thing.

[AZDesertRat]

You will never get a true 0 TDS from RO only water. RO is a 90-98% efficient drvice so can never remove everything from the tap water. Hobbyist grade TDS meters have a 2% +/- of full scale (0-999 ppm) accuracy level so can be off, especially on the low level like RO or RO/DI. This is why it is important to keep the meter clean and calibrated.

 

In order of purity

1. RO/DI

2. DI

3. Distilled

4. RO

.

.

10 Tap

[nicoles 215]

i use sink water w prime and have no algae growth.

[empresto]

2 hours ago, nicoles 215 said:

i use sink water w prime and have no algae growth.

It should be noted that everyone's tap water will be different. For example, where I live, the average TDS over a given year is around 500, with ~10ppm of that nitrate, 2ppm ammonia, 1-3 ppm phosphates depending on the season, and 1 ppm copper. The rest is mostly calcium carbonate and <20ppm magnesium with about 15ppm things I can't find on my test kits. Certainly not going to introduce that mess to my reef, let alone drink it before it goes through my RO system.

Also, having seen what the seasonal fluctuations can be with rain, snow, freeze, thaw, etc, you might get lucky for a few months with your tap water, and then suddenly one day your tank starts to go south because your tap water changed with the season.

Now, if you've done your testing and research and find that your tap water is sufficiently safe for your pets, great! I'm jealous of your water source.  But, for the other 99.9% of tap water situations, a well maintained RODI system is certainly the best, most consistent, option, and eliminates the risks of most other sources for water.

[natedg200202]

If you do the math, setting up an RODI system will pay for itself pretty quick (compared to fish store RODI or WalMarts water). 

[jarviz]

 I live in NYC and have supposedly one of the cleanest tap waters out there. TDS is about 35ppm out of the faucet. I did a phosphate test with fresh batch and it read 0.9 (or above the range of the Hanna Checker). There's also silica and other impurities, metals that may not be easily removed with a Tap Water conditioner. I never tested nitrates but i don't think there is nitrates in tap water (but i could be wrong). 

 

It's weird though because when i tested phosphates of my 2-month old tank, i was getting about 0.15 phosphates (with phosguard and macros). so my tank was actually ok for the time being, but i think all the phosphates were just binding to my rocks and sand.