Your local water contaminants list by zip code

Admann · Oct 23, 2019

I thought this might be helpful and remove some of the mystery surrounding providing suitable water for your reefs.

I found this link to a website "www.ewg.org". It shows using your zip code what contaminants are in your municipal water supply and what will remove them.

Now I understand why my anion DI depletes so fast. You will never drink unfiltered tapwater again.

homer1475 · Oct 23, 2019

Interesting.....

I knew our water was pretty clean, but according to that, we only have 2 contaminates. Nitrates and total trihalomethanes(whatever the heck those are lol), of which both are removed by RO.

Righteous · Oct 23, 2019

A lot of the contaminants they show are side effects of chlorine disinfection. I appreciate the insight this gives, but also take the "300x" or whatever numbers with a grain of salt. It's not clear how they get to those numbers, but most of them don't have legal limits, and most have not been shown to have any health effects at those levels. Basically don't immediately freak out if your water is shown to have 300x trihalomethanes. Mine shows 328x but is actually half of the legal limit of 80ppb. So... just always use at least a good carbon filter for drinking or cooking.

But great source for understanding what your RO/DI is dealing with!

BTW... if your DI is depleting fast, I'd always double check your RO membrane and TDS after the RO before the DI. A good RO should really take out most stuff and keep your TDS in single digits. Fast DI depletion is almost always a problem upstream in the RO not running efficiently.

Randy Holmes-Farley · Oct 23, 2019

I would add that by far my biggest concern with tap water is copper, and copper can easily pass epa guidelines while still being way too high for a reef (0.5 ppm, for example).

Admann · Oct 23, 2019

BTW... if your DI is depleting fast, I'd always double check your RO membrane and TDS after the RO before the DI. A good RO should really take out most stuff and keep your TDS in single digits. Fast DI depletion is almost always a problem upstream in the RO not running efficiently.
[/QUOTE]

RO averages 390tds in/ 6 out to the DI, the anion depletes the fastest, but I still get good life out of it. Now I know what I'm removing. Bad things.
When I worked offshore we ran and maintained 2-10,000 gpd RO units to produce our freshwater for bathing, equipment cleanup/washdown and cooking. It was kind of funny when the engineers found out the piping supplying the bunkhouse and every other freshwater supply pipe on the facility doesn't last long when you have 0 tds. We learned rather quickly that we needed to add a mineral to the product water (potable) keep it from leaching them from the pipe. That was a long time ago.

Righteous · Oct 23, 2019

I seem to be lucky.. no copper or other heavy metals in mine (tiny amount of aluminum). But lots of chlorine byproducts. I need to make sure I stay on top of carbon block replacement to maintain my RO.

Thanks again for the link!

Silent · Oct 23, 2019

My water has arsenic at elevated levels.

Dkeller_nc · Oct 23, 2019

Admann said:
You will never drink unfiltered tapwater again.

Quite the opposite, actually. Chlorine and chloramines are put into municipal water for a reason. Filtering it out on an on-demand basis may be sort of OK as long as you ensure that the carbon cartridge used to do it doesn't grow a basketfull of nasties like pseudomonas and vibrio. But it's pretty tough for the lay person to make that determination.

flsalty · Oct 24, 2019

The only thing a RO/DI filter won't take care of in my water is chlorate. All I can find on that is there is no way to filter it out. Can't find anything on it's effect on a reef tank.

Righteous · Oct 24, 2019

flsalty said:
The only thing a RO/DI filter won't take care of in my water is chlorate. All I can find on that is there is no way to filter it out. Can't find anything on it's effect on a reef tank.

What levels are in your water?

Dancingmad · Oct 24, 2019

Randy Holmes-Farley said:
I would add that by far my biggest concern with tap water is copper, and copper can easily pass epa guidelines while still being way too high for a reef (0.5 ppm, for example).

I just checked out the water report out of curiosity (I couldn't find my water system on OP's site). How concerned should I be if the report says copper at 1.3ppm? I have a RO-DI system.

BiGGiePauls33 · Oct 24, 2019

Here's mine:

vetteguy53081 · Oct 24, 2019

Very nice info!!
Glad i have well. The area water is horrible and we have one of the best filtration plants in the Midwest!! Nitrate and nitrite is almost at 3 !!!!

vetteguy53081 · Oct 24, 2019

paja3 said:
Here's mine:

O U C H !!!

BiGGiePauls33 · Oct 24, 2019

vetteguy53081 said:
O U C H !!!

Yup, no wonder why everyone in town dies of cancer, my Mom included.

ndrwater · Oct 24, 2019

I'm going to DIE!!
Anaheim water sucks.. but I knew that...
Based on the results from the link, it's amazing my corals live at all...

ndrwater · Oct 24, 2019

vetteguy53081 said:
O U C H !!!

Just to make you feel better, look up 92806 where I live.....

Righteous · Oct 24, 2019

flsalty said:
The only thing a RO/DI filter won't take care of in my water is chlorate. All I can find on that is there is no way to filter it out. Can't find anything on it's effect on a reef tank.

Found this paper:

https://www.environment.gov.au/epbc/notices/assessments/2007/3385/pubs/25chlorate.pdf

Chlorate seems to effect brown algae the most in these studies.

From the paper:

“Clorate is rendered toxic by conversion to chlorite via nitrate reduction. Baltic Sea algae are mostly nitrogen limited and chlorate can easily take the place of nitrate. Chlorate and nitrate interact such that cells do not discriminate between the two.”

The chronic exposure levels for some brown algae’s were as low as 5ppb. That does give me some pause concerning coral Zooxanthellae.

My water is supposedly 14ppb. It seems like chlorate is stable is seawater so it might build up over time.