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RO/DI water


Blue Ring
Nov 10, 2004
Hi all - please excuse our ignorance but our LFS have not said anything about needing RO water etc and my knowledge on the whole process is limited to say the least. :cry:

Any and all advice on this would be excellent. :lol:
If you don't use RO water you will be plagued with constant battles with algae and ph unbalances...it is worth every penny ! You should be able to buy it from a water store, or install a small unit at your house without being breaking the bank also...unusual that your LFS doesn't use it ???
LFS may use it, but we have spoken to them about setting up octo tank & they havn't mentioned it.

Just reading thro old posts I now have another big query re copper.....

We are setting up a second hand tank, and I've just checked with previous owner who has used it for FW and has in the past added vitamin/mineral supplement Esha Mineral which has 9mcg copper per 20mils.

What do we do about this?
According to Dr. Ron Shimek on Reefcentral, the following procedure will decontaminate your tank:
As long as you are going to break down your main tank, let me suggest the following procedure which will help removed adsorbed metals, and persistant organic chemicals.

Once you have removed everything from your system (all critters and substrate), but still have the pumps and such hooked up.

First, disconnect the plumbing to the refugium and isolate it from the rest of the system. Do not reconnect it until you have finished the procedure below.

Caution: Be very careful with both the acid and the bleach these are hazardous chemicals. Wear rubber gloves and disposable clothes...

NEVER allow the acid and bleach to mix, if you do, you will generate chlorine gas and this will ruin your whole day - and your lungs.....

Open some windows and make sure the room is well ventilated and then...

Go to your local hardware store and get a gallon of muriatic acid. Fill the tank half way, and then add the gallon of acid to the water. Fill the tank the rest of the way. Turn on the pumps and let the system circulate for a couple of hours. This acid bath will dissolve any adsorbed metals from the system. Then drain the tank of all the acidified water (it is safe to go down the drain). Fill the tank with fresh water and let it circulate for an hour or so, drain again. Fill the tank a third time, and add a gallon or two of bleach. Let it circulate for a couple of hours. This will remove any organic build up. Drain this solution out. Then fill and circulate the tank with fresh water and a super dose of dechlorinator. Drain this again. Dry the inside of the tank. If the tank smells of bleach repeat the last rinse.

At the end of this procedure your tank should be free of any contaminants.

Also, don't ever use any type of soap to clean anything for your tank. Again quoting Dr. Ron:
Soaps are not reef aquarium safe, they leave films and dissolve the animal membranes.

Dilute muriatic is perfectly safe in aquaria - and in your coffee pot. It is simply HCl gas dissolved in water. Certainly, it is volatile. That is why I suggested you do the procedure in a well ventilated place.

Frankly, for marine animals it is far safer for the animals in your tank than is anything containing soaps or other surfactants. The procedure I described will not harm silicone, plastics, acrylic or powerheads, and it will remove all mineral and organic contamination from your tank.

Thank you for your help.You learn something new every day.Thanks again.One last ? Doc. Ron if those surfacants were used even soap for that matter if rinsed well enough it could be removed right? I mean it shouldn't bond to the silicone would it?

The memory of soaps linger on. One of the rules of thumb in a marine laboratory where you want to raise delicate animals is that once a piece of glassware is washed with soap, it is discarded. It is simply not worth the trouble to try to clean it.

I generally consider soap in an aquarium to be as lethal and toxic as heavy metals.

In other words, you would have to decontaminate the tank (with the acid-bleach procedure I described) to be sure you removed the soaps.

For more information, I suggest going to reefcentral.com and doing a search on either the Ask Dr. Ron or the Reef Chemistry forum for "copper decontamination" with the date range set for any date. You need to be a registered member there to view the expert forums, but it's free and the info there is worth it.
hmm. I somewhat disagree with that...silicone has been found to contain copper level lethal to cephs after such treatments, it is easier to either get another tank, or strip out all of the silicone and replace it with 100% silicone of aquarium grade...better safe than sorry...
As far as using RO water, I just set up a 10 gallon tank using well water, and I discovered my alkalinity was off the scale. Turns out that my well water had the level of Alkalinity recommended for mixed salt water to begin with, so when I mixed it with the salt, it ended up too high. I only setting up the tank for pods and algae, so I will not be out a lot of money if they die from it (although I am trying to correct it before that happens), but with an octo, the amount of money you spend on RO water will be heavily outweighed by the abount of money you could lose from not using it.

Just my :twocents:
i also disagree with the reef central info - not that it couldnt be right but firstly that is an awful lot of work!!!! and water and chemicals!!!

second, as it has already been said it is better to be safe than sorry - maybe replacing the tank and keeping pump etc is the way to go - read lots and decide for yourself but the consensis on tonmo is that it is near impossible to rid the system of copper so that it is safe for cephs - ultra sensitive due to high expose surface area (dr wood i think said that)
cheers for all the info! :notworth:

Still trying to work out whats best to do. I agree that the acid/bleach method uswes an awful lot of chemicals, and theres the possibility it won't work.

Trouble is we got a really good deal on the tank,and just don't have the money to buy a tank of that spec from new.

Are copper tests sensitive enough to pick up traces of copper if I do get the tank up and running? Obviously I'm not going to put any animal, specially not an octo in a tank that would be harmful to it. :cry:
everyone has their own opinion on this one im afraid!

you said that there was definitely a copper med used in the tank which probably means it is there wether or not it can be detected!!

i completely understand the tank price issue however emptying the tank after set up and ceph death is much more costly - but perhaps selling it via the trading post and hanging out for a bargain tank - try for sw tanks to be sure of copper and ask about history use

i waited 8 months and now have a great 5' setup with everything i wanted for under my budget - it seems like a very long time but what i wanted was VERY specific so you may have luck in just a few weeks

try asking people who have decomisioned tanks and are selling if they will separate components or if it is cheap enough just get the lot and do what you want with the rest!! you might pick up some cash for it - all the best!!!

good luck - id appreciate others to post on the topic cos mine is just one opinion.
Been to LFS to look at exactly what has been used in the tank, and what they think. Seems like its a trace element supplement rather than a copper med, and Cu as a trace element is in Tropic Marin, the salt we use.

Been advised to set up tank with freshwater (pref RO/DI) and then test it numerous times.....

By the way, asked the LFS why they didn't use RO water. They use rainwater for all their tanks (yes it rains alot in the uk!!!).

I reckon we will use DI water rather than RO as I can't find anywhere to sell RO water, and the process seems to be v wasteful. Can at least buy Di water locally!
If push comes to shove what about goin over the existing silicone with new?? Only an idea but if you manage to completely seal over the old with new then its water tight and none should get through.

ok your not guaranteed but you are limiting the possible damage.

Does anyone reckon the copper would migrate through the new :?:

My tank has got copper handles on the doors and lid, even thou it was designed for a reef. What knob-shiner the bloke was who designed that!!!

ON the RO/DI ive got a mate who has gone nuts and has a 9 stage filter doin both RO and DI and his water is purer that pure puree. If I ever get my tank up an goin thats were I plan to get mine from. But the point I wanted to make was that he swears by the minimum of a 4 stage filter.

Prob why you see so many 3 stage on ebay. Any thoughts :?:

If you were to get one Naomi&Joe you can easily fix in a self tappin tap to your cold water pipe under the kitchen sink and run a little pipe out from there to create it. Easy he says :lol:
Regarding the copper question.... we thought about siliconing over, but my thoughts are that if the copper has been absorbed into the old silicon, then if we re-silicon the copper will eventually leech out into the new silicon, and so into the water???

So whilst we could have tested for copper to our hearts content before putting an octo in, after a while there could be copper getting back into the water, and knowing my luck this would co-incide with having just put Octo in. Any thoughts on this anyone????

As for the RO/DI thing... we will definitely go with one or the other!!!! Just a question of whether we get an RO unit with deioniser (yep Scouse reckon your ebay theory is correct - but also see WWW.RO-MAN.COM), or a DI unit, or just buy in DI water....
i also dissagree with Dr Ron's ramblings but i do that a lot these days :smile: LOL

The best example of copper in a well washed system causing a problem was by Dr Roy Caldwell. He had major problems with a set up and it was traced back to a copper treatment in the distant past.

There is only one way to make sure that there is no copper and that is to get a new tank. There are no guarantees otherwise.

Its also worth noting that RO units beed replacement catridges from time to time and an eBay one may need new ones?
I just buy RO water...half the time, the store doesn't even charge me at all since I am in and out of there so often ! (one reason why shopping at a lfs really pays off...)
So, back to the copper question...

We have got tank up and running, and have had polyfilter (Underworld products) in for a week. It shows no trace of copper at all. We have tested for Cu using Salifert test kit - which I have to say does not go overboard on the instructions/explanation/rationale side of things to say the least - and this is also showing completely clear.

We are kind of thinking that copper in this particular tank is not a problem....

Any thoughts people? Need to know cos if it's ok then we will go and buy more live rock v soon... :smile:


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