RO Water

6 May 2007
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Everybody is RO water this, RO water that. I have used about 200l of RO water in the last 5 years, and my tank looks good, Is RO water really that important or am I just very lucky with the water I have been using ??
At the last GRC meeting many guys said they don't use RO, but why risk it? We have so many variables in our hobby that IMHO one should try and get as many of them to constants. I think thats why we use RO. Wessel you might be lucky now but 2morrow Randwater decides to do something funky with our water and then you have problems. I think this is a case of err-ing on the safe side.
Ok I asked Robin (Midasblenny - who we have no doubt knows what he is talking about x 100000000) the same question. I was under the impression that tap is going to add PO4 dunno why. Robin's answer was that by using tap water we are introducing heavy metals into our systems. Not a problem now BUT someday the build up of heavy metals are seriously going to cause havoc with your corals. Now I dunno what the time frame is on someday but it could be 5 years 11 months 30 days, 11 hours and 59 seconds.
I had a look at the specs and typicaltest results for water from Ekuruleni.

Whiel the results themselves when I checked were actually very good, I was more worried about the specification limits.

Eg. a typical result for nitrate may be 0.2 ppm, but the spec is <50ppm (this may be a bit of an extreme exampel, but just to illustrate the point)

This basically means they are allowed to go up to 50ppm nitrate before alarm bells go off. Same applies to most of the other specs as well.

So your local water treatment works may just be suppling good water, but one day a relatively poor batch gets passed(in spec but at highest levels of impurities). Then what?
dude im a stingy guy when it comes to RO and im considering buying one.... the water down here is just getting worse.... even a little too hectic to drink...
Just get an ro unit, then you can have healthy drinking water aswell.
ive only started using RO from november 2006.i always used tap water with success for almost 13 years of FOWLR systems.after reading alot,and met marco decided ide rather be on the safe side.
Just to give you an example here. I was getting, what I thought, was RO water. It turned out the owner of the shop has not changed the RO membranes in over a year. Does not seem so long BUT according to Marco (the king of RO water) once the membranes you WILL get kak water. I took a TDS meter there and measured the tap water. I got a reading of 46. I went to his 'RO' water and that read 52.
Wizzard then got his own RO unit. The water had a TDS reading of 0. Once I started using that water I had a HUGE turn about in my tank. Coralline started growing quickly, algea blooms slowed, corals grew quicker and the tank looked better.
I feel I was using tap water to top up and I could see my tank getting worse. Using decent RO water and a good brand of salt is the best thing.
well put gavin , my mate has the the similar size set up as mine , similar lighting etc etc ... he wants to kno how come i have no algae probs , said ro water , kalkwasser mix on top ups ....he decides to prove me rong , buys sailfin tang , fox face , still got algae . then he decided to use ro water and its helping big time !!! by the way same guy who told he's been keeping marines for 15 yrs and the jebo is the best skimmer !!! i wanted to kick his arse for his arrogance !!!!
I have met some people like that. I had a jebo and it is fine for a 1 litre tank maybe. I really disklike Jebo but that is my opinion.
Question, considering the cost of a RO unit, is there any viability in just buying distilled water? I am assuming it is as inert as RO water? Would that not be cheaper?
You can buy single distilled water from places like Protea or Crest but it's about R1.00/litre and then there is still a drum deposit you will probably need to pay.

Will be much more convenient and cheaper in long run to buy an RO, especially if you have a large tank and perform regular water changes.

If you have a small tank it may be better to just purchase RO water from your LFS
I agree, i currently buy RO at 80c/L but when the big tank comes I'm putting in a RO unit. I would imagine you'd pay of the RO unit in a month if you compare it with the 300L per week for water changes and say 25L per day on evap. Ouch!!
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