So I Got My Tap Water Quality Report...

[Alaskan Reefer]

...and I'm wondering if it's time to finally buy an RO/DI system. I've been successfully keeping a mostly SPS reef for many years on my local tap water, but I'm pretty sure it's unusually pure. I do treat my water with dechlorinator of course, but honestly that's it -- dechlorinator and into the salt or kalk mixing can. Here are the highest detected levels of each contaminant in my community's tap water, all of them range from not detectable to this as the high point...

Turbidity = .94 NTU
Organic Carbon = .63 ppm
Radium = 1.13 pCi/L
Antimony = 1.9 ppb
Arsenic = 5.22 ppb
Barium = .10 ppm
Chlorine = .94 ppm
Chromium = 2 ppb
Copper = .25 ppm
Flouride = 1.5 ppm
Lead = 2 ppb
Nickel = 2.4 ppb
Nitrate = 1.98 ppm
Selenium = 1.22 ppb
Haloacetic Acids = 4.6 ppb
Total Trihalomethanes = 5.6 ppb

I don't know much about chemistry beyond what I measure in my tank, and I know 0-1.98 ppm of nitrate is very acceptable to me -- the tests I've done on my fresh salt water mix have always been undetectable with a Salifert kit. Still, I don't know if anything else here is of any significant risk. As mentioned, I do dechlorinate, and I typically run carbon and polyfilter in my system. So, my question is, buy RO/DI, or get some more frags?

[VacavilleFC3S]

buy an ro/di, you haver .25 ppm copper thats not good really.

[Alaskan Reefer]

The copper measurement comes out of random customer taps, so I'm sure a lot of the measured numbers include household plumbing corrosion -- and that's the peak measurement among hundreds of random households, it ranges from 0-.25ppm. That may be good enough reason alone for me to get an RO/DI, my own household corrosion -- then again my house is less than 20 years old. That said, though, carbon and polyfilter seem to have kept any copper I might have from harming any of my critters -- but you're right, the possibility of copper is what worries me the most and has me thinking it might be time to change over to RO/DI...

[VacavilleFC3S]

i'd go ro/di since it brings all those # to pretty much 0

[afboundguy]

I agree with RO/DI... IMO TDS is the way to measure water to see how clean/pure it is...

[luther1200]

The only 1 that really concerns me is also the copper. Thats in ppm not ppb.

[Alaskan Reefer]

Thanks for the responses!

I have no way to measure TDS, but I'm guessing it's pretty low if the turbidity is .02-.94 NTU. Then again, turbidity doesn't measure dissolved solids, only suspended ones, but still gives an impression of purity.

The copper at 0-.25 ppm is definitely why I'm considering this -- what's a good test kit to use, Salifert is what I use for everything else. I don't see anything else particularly damning for a reef tank in that list of contaminants -- to what degree does GAC / polyfiltering really take copper out of water?

[Alaskan Reefer]

Also, with water at this level of contamination, how long should I expect RO/DI cartridges in, say, a Bulk Reef Supply 5 stage to last?

[luther1200]

I would think your RO/DI filters would last for 8 months maybe a year. But you can get a hand held TDS meter for like $30. The membrane will last even longer.

A Polyfilter will change color if there is copper present. I don't know exactly how much though. And if you were going to get GAC I highly recommend BRS ROX carbon. It is excellent.

And if I was going to get copper test kit I would get Salifert.

[Jack01]

Originally posted by Alaskan Reefer
I've been successfully keeping a mostly SPS reef for many years

IMO, if it isn't broken don't fix it. My water is unusually pure aswell. 12tds or less. I've been fine also.

[darkdruid]

If everything in your tank is doing fine, don't mess with it. If the copper levels were a problem, you would already be having issues.

[Alaskan Reefer]

Good point Jack and darkdruid. Most of my recent SPS frag additions in January and February have doubled or more in size -- I think I'll let it roll for a while and be thankful for the water quality.

[luther1200]

I wouldn't. Most communities do a cleanout or algae treatment at some point. And they don't always let the puplic know because its not harmful to humans. But could have a devastating affect on a reef tank. You could be fine, but then again they could treat the water and that would be it. I'm not saying it will definitly happen, but it has definitly happened before.

Maybe you could call your local water company and ask if they ever do anything like that.

[greenbean36191]

There are really no hobbyists tests for copper that will be much use for you. They don't have the resolution required to test for toxicity. They're really meant to monitor therapeutic levels of copper which are orders of magnitude higher than the levels of chronic toxicity to inverts. I suspect the utility isn't using a much more sensitive test if they report their results in ppm, so a minimum reading of 0 would not give me much confidence.

[darkdruid]

Anything other than trace amounts of copper can cause problems. But even natural seawater contains copper, which is required for the orgsnism's health, and without it, most marine creatures, corals included, would die. It's excess amounts of copper which can cause problems.

He has been running his reef with no apparent problems long term. It doesn't matter what the tests say or how accurate they are, it makes no difference whatsoever. If the levels were elevated enough to cause problems, he would already be having problems and he isn't. The best water quality test you can possibly use, better than anything on the market today, is your tank. If everything is happy and healthy and growing, the water is fine, don't screw with it just because someone else thinks you should.

[luther1200]

How do you know that? Does he have a test from a while back with the same readout? If not it could potentially be a problem if the levels accumilate.

[greenbean36191]

He has been running his reef with no apparent problems long term. It doesn't matter what the tests say or how accurate they are, it makes no difference whatsoever. If the levels were elevated enough to cause problems, he would already be having problems and he isn't.

No. If the levels were high enough to cause acute toxicity it would have been apparent before now, however the toxic levels for chronic exposure are much lower and issues take a long time to become apparent.

[darkdruid]

I hate it when someone disagrees with me and makes sense. I can't argue with that because you are 100% correct. Long term exposure to lower levels can be just as destructive as higher concentrations. Current tank conditions seem to show that there are no adverse effects yet, but that doesn't guarantee it will stay that way in the future.