Rain Water?

[king_neptune]

diddnt read through the post. but im sure everyone already said its a bad idea. they are right, lots of man made chemicals in rain water depending on your area some places are worse. our rain water has jet fuel exhaust from the military cargo planes that fly over head all the time.

 

[coral keeper]

I read the whole thread... Hmmmm.... Sounds like an experiment to me. I have a TDS meter, so, when it rains I'll check it and post the results here. It won't rain where I live (California) any time soon.... Also, someone might want to remind me every once in a while so I don't forget about this.

 

[aquaknight]

Originally Posted by meowzer
http:///forum/post/3138389
AQUA...Do you think there would be other impurities in it that a tds meter will not pick up? metals? pesticides? isn't a good part of rain water made up from evaporation of water from the ground? What is in that water in the ground?
Also....a lot of rain water picks up the pollutants as it falls....
Sorry...I am having trouble wording this..LOL...BUT I think you know what I am getting at
anyone??
A TDS meter works by applying a charge to 2 probes (or more). One probe is negatively charged, one positive. Positively charged ions (particles, such as calcium, sodium, etc) are drawn to the negative probe. And vice versa, negatively charged ions, (chloride, sulfate) are drawn to the positive probe. As these ions are drawn, because they are charged one way or the other, they constitutes an electrical current. The TDS meter then measures how much current is passing between the probes, vs how much should be going through.
After that, my brain farted, and I forget if more crap in the water increases or reduces resistance, but either way.
So yea, you nailed it, they will not detect any neutral compounds. Pesticides, ammonia, most "organic" things, etc, can't be measured.

 

[aquaknight]

Fun fact/FWIW, Mobile, AL is the wettest city in the contiguous 48 states, more then Seattle, Portland, or New York.
So I'll probably post up my results tomorrow

 

[mikecurrin]

I cant wait to see the results that someone posts.

 

[aquaknight]

I just did some 'light' tests, but they are certainly "interesting." Trying a couple different things out, mostly collection issues, but should have a nice report tomorrow.

 

[mikecurrin]

I can't wait to hear back from you.

 

[volreefer]

I've measured the water in my rain barrel a few times over the past two weeks. I've read 9 and 10 respectively on my tds meter. This is not much higher than my r/o unit. Although tempting, I'm not sure if I'm willing to use the rainwater just yet. Beyond the acid rain issue, the water may be contaminated from the roof. I live in the outskirts of Knoxville so there may be a fair amount of pollution raining down.
I was hoping someone has experience with rainwater in their aquarium. It would be nice to use my collected rainwater--- I have three rain barrels with 50+ gallons that I use for the garden.

 

[aquaknight]

Alright, the biggest problem by far is collecting significant amounts of rain amount. I had around 7 glass cups and 2 measuring cups, as well as a 5gal bucket. We have a 'steam' setting on our dishwasher that cleans the hell out of the cups. Usually just the slightest dirty container can add a lot of TDS to your readings. I used a Hanna pen-style TDS meter
Some parameters;
My tap water usually is 250ppm
Water out of my RO is around ~7ppm
Out of the DI is 0ppm
The first batch I tested was the 5gal bucket, which yielded 20ppm. This sat for all three days, so I have no idea whats in there.
About 3 glasses was enough to test. The average was around 12ppm, which the best testing in at just 10ppm.
Lastly just for kicks I measured the runoff from the roof. Theyre asphalt shingles, and measured around 50-60 ppm.

Just spend a couple moments on google just checked other people's results and they're nearly the same, into the 10-15ppm range. I also tested ammonia, which was zero across the board (seachem/sailfert tests), and nitrate, which had trace amounts.
In conclusion, I just can't see anyone practically using rainwater. Without something extremely large, like a roof, just sticking a bucket out there, will take forever. Especially depending on what size tanks you have, etc, when a water change consists of more then 20gals of water. Also, there are ton's of farms around me, in every direction. As noted above, there are some pretty crucial things that a TDS meter does not read, and without that info, I'd never use the water.

 

[big]

Yes there is a tiny bit of sulfur .and some particulates depending on location and how long after the rain starts you measure the specimen. Yet these levels of stuff are below what my RO water from my well is after a few months without new filters.
I have collected rain water from down spouts for well over 30 years for use in tanks. Just a clean roof and clean downspout with a method to collect is all that is needed..Yes I do have a RO, but if rain is available I use it, and no wasted water from the RO.. Here an average of 3 to 7 PPM sometimes less) one hour after that start of a steady rain...... Just do not use the first part of a rain, let the rain pre-clean the roof and air first..
In the old days it was the source for almost all Show Guppy waters..These show quality fish needed the softest water available, and rain water was it......
When using it for my Reef I simple add a tablespoon of baking soda to each five gallon bucket collected to help buffer and raise the PH to a level just over 8 .....
Jut remember, that ocean contains more impurities and heavy metals than just about any other place on earth............Ever see one of those underwater volcanoes on TV spouting out sulfur?

 

[mikecurrin]

In previous notes about how the ocean is a much bigger area to dilute that amount of impurities, one would think that in a smaller (55 gal) that would not be enough space to dilute. However seeing these results from the hard work of everyone, it seems do-able. Maybe in a case where you are out in the middle of nowhere and the closest place that sells RO is a good 30 min drive, a little could no as a top off...But the question I guess would be To try or not to try...

 

[meowzer]

WELL Mike...it seems our storms have passed for now...LOL....Wait for the next set...
I still wouldn't, but it's up to you...also once you collect it you have to keep it clean, and not let it get stagnant...IMO...too much trouble

 

[big]

Originally Posted by Mikecurrin
http:///forum/post/3140354
In previous notes about how the ocean is a much bigger area to dilute that amount of impurities, one would think that in a smaller (55 gal) that would not be enough space to dilute. However seeing these results from the hard work of everyone, it seems do-able. Maybe in a case where you are out in the middle of nowhere and the closest place that sells RO is a good 30 min drive, a little could no as a top off...But the question I guess would be To try or not to try...
Another issue that I should have addressed here is where one lives and the source of the rain they are receiving comes from.....
For examples, If one lived just east of a big industrial city like Pittsburgh, or a big coal fired power plant to your immediate west and such..... Rains coming in from the west would naturally contain more crud to deal with...(like many of our short duration winter storms north-west winds off of the lakes cause..)
BUT...If like many here in the eastern states most of our systems generate their precipitation over the Atlantic, then dropping the rain here on us....... These systems contain a very low PPM content normally, possibly better than some of our RO set ups can produce......The same should hold true to others living within a few hundred miles of a coast line with ocean generated precipitation.
Again I have used both rain top off and PC water for years off of my downspouts. A good summer wet spell can give me 50 gallons in a couple of hours. Yes in the drier periods I do use RO, but the rain is free with none running down my drain the way my RO does..

 

[mikecurrin]

I have to agree, for me it depends on the wind direction. I live near Dallas, TX, so I get a little everything, Coastal showers, Rain from the Mountains of Colorado, and the occ storm from OK. So I guess it would just depend for me and having a good filter to still run it through would not be a bad idea, but like everyone we go through dry spells here too. But Thanks everyone for your input and help.