Ro/di

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tawolcott

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Ok, so my RO/DI arrived the other day. After all the back and forth (both decision and the **** store for water) I decided to join the cult.

One question I haven't seen asked is related to the switch over. Should that be a gradual thing. First week 4to1, next week 3to1, etc etc..

I've got a 30g FW and 75g FOWLR.

Just unsure if there needs to be an acclimation period for the different water content. Would seem to me the same rule should apply as far as acclimating the fish into the tank (in general of course, I have no intention of dripping water in and out)

Thanx in advance
 
Not sure I understand the question. With a new RODI system you need to flush it by wasting the first 3-5 gallons of water it makes. Then use the RODI water to replace the water that evaporates, and for mixing a pwc batch.

I'm not sure about using RODI water for FW tanks. You may want to check into that.
 
Absolutely!! Now is the time to be doing your PWCs with your new RO/DI water! Top off with fresh RO/DI water too!! Your tank will thank you!
 
Let me make one comment here:

Use the RO/DI right away with the salt tank.

Do NOT use the RO/DI with the freshwater tank.
 
Pat can you explain, I'm not sure I see the difference for this issue between SW and FW?
 
Found this comment on Algone.com:

"RO water can be used for marine and reef tanks as the salt mix provides all the essential minerals and salts needed. Straight RO water is not acceptable for freshwater as it lacks essential minerals and salts. You must learn how to adjust the water chemistry if you use RO water for freshwater tanks."

Comments? Really gonna PO me if I shouldn't use for both
 
Yes, I have always heard exactly that, which is why I cautioned about using it in FW till you heard from others. RO strips too much form the water. Best to use tap for fw.
 
Hey,

Just got my RO/DI last night from Air, Water & Ice. I plan on using it for both FW and SW. I'll bypass the DI filter for FW use. Our well water is very hard 15GH/8.5 PH.

Our test kit recomends R/O treatment to lower these numbers. It makes sense to me.

Dave
 
From wetwebmedia:

I have read that you should not put RO water in freshwater tanks, then some articles saying you should?
<The idea is that you should not use untreated RO water, as there is no mineral content. There are several buffering powders specifically for freshwater tanks that can achieve this. Another method, which I personally employ, is to use 2/3 RO waste water to 1/3 RO water for my freshwater tanks. The RO waste is dechlorinated already, and it cuts down on the wasted water!>

and suggests using something like this:
Search Results for electro right

Through all the discussions here regarding Ro/DI, I don't think I ever saw any reference to not using for FW
 
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RO/DI water is 99.9% pure water. H2O and nothing else. I have a 55g FW planted tank that I refill and do water changes right out of the tap. I use my RO/DI for my SW tanks only. I put the elements and nutirents in the water via the salt mix. Fish and plants need elements to live so if you are using RO/DI water in a FW tank you are going to have to supplement the water in some way. I have no idea what that is but I'm sure there are products out there to do it.

SW - RO/DI
FW - TAP (treated if you have chlorine in your water)
 
Hey,

Just got my RO/DI last night from Air, Water & Ice. I plan on using it for both FW and SW. I'll bypass the DI filter for FW use. Our well water is very hard 15GH/8.5 PH.

Our test kit recomends R/O treatment to lower these numbers. It makes sense to me.

Dave

In your case I suggest playing around with your test kits one day.

Start from a 50-50 mix of RO/DI water and well water. Run the PH and GH/KH tests on this mix...adjust the percentage mix until you hit the numbers you want and remember this mixture for future water changes.

As others mentioned if you use RO/DI water (or even just RO water) you will have to "dose" some of the minerals and the like back into the water. If you want to strictly control what goes into your water (running a science experiment for one of your children's school science projects perhaps?) then go ahead. If you have extremely hard water than use a mixture. If neither case applies I would advise against it...Just the use of an absorbtive media like Purigen was pulling too much stuff out of the water for my plants to grow healthy (though I did not see any adverse effects for the animals).
 
I use RO/DI for my 2 planted tanks (FW). Our county has a warning for our water "not for aquarium use". I also use for my SW tanks too.
 
Patryugi

I like that idea of mixing tap & RO to come up with a comprimise of chemicals for FW use. Our area [region] is high in limestone deposits, which contributes to our high ph. I don't know what causes the hardness.

Is there an ideal for ph & GH, or do you tweak paramiters to suit your needs? For instance, we've never been able to keep discus. Is it realistic to manufacture water which these fish will thrive in?

Dave
 
It's really neither of those things. For some time I've read on here about the advantages of ro/di. One might even say that the majority of posts on the simply say that's all you should use. That I can remember, I never saw a post making a distinction between FW and SW, nor anything on dosing essentials that are removed. Even from the get-go of this post , which was just a question of if I should mix the 2 for awhile to ease into the 'new' water the answers were just do the switch.

I never gave it a second thought until someone mentioned not to use it for FW; the I went looking to validate the statement. So, no it's not a science experiment, I don't want to 'play w/ my numbers.

However if you consider your time to be worth something I would wonder what the true cost benefit number is for the ro/di filter once you factor in dosing, testing, mixing time and costs. For FW it sure isn't filter the water - use the water as compared to using bottled water as I do now which is open the 5g jug and siphon in.

Too late for me now, as I've already made the plunge so I'll use it for both FW and SW regardless.

For others when the ro/di discussion is broached, it might be useful to make the distinction before recommending it.

And for the record, it was Bob Fenner over at wetwebmedia whose posting first recommended mixing the two first in this thread. Credit where credit is due
 
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Well for what it's worth I started my SW tank out with RO/DI water, I use it to mix with and I use it for my top off. My FW tank I just use water right out of the tap (I'm on well water and it is prestine).

If you want to read about a situation using a de-chlorinator on a SW tank go to oregonreef.com and read about what happened to this amazing 800gallon reef.

I'll stick with RO/DI water 100%
 
From Drs. Foster and Smith
"[FONT=Arial,Helvetica,sans-serif]Reverse osmosis removes virtually everything from tap water, including essential minerals your aquarium inhabitants need to flourish. Depending on the type of aquarium the RO water is being used for, it may be necessary to add these essential minerals back into the purified water...However, freshwater aquariums require re-mineralization to achieve the desired pH. . . . [/FONT]
[FONT=Arial,Helvetica,sans-serif][/FONT]
[FONT=Arial,Helvetica,sans-serif][FONT=Arial,Helvetica,sans-serif]In some areas, especially in regions that have limestone deposits, well water will contain high levels of minerals, making the water "hard." Water hardness is closely associated with pH and influences the ease at which pH can be altered. The high mineral content functions as a buffer and counteracts the effects of pH conditioners.[/FONT]
[FONT=Arial,Helvetica,sans-serif]In order for pH conditioners to work properly, the minerals must first be removed from the source water. The most effective way to do this is through the use of a reverse osmosis unit. They can remove up to 99% of the minerals and other impurities in your water.[/FONT]"[/FONT]

[FONT=Arial,Helvetica,sans-serif][/FONT]
[FONT=Arial,Helvetica,sans-serif]Try a Google search on "RO water in a fresh water aquarium" for more sites with similar information.[/FONT]
 
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