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PRinWarrenton

Collecting Rainwater to Make Saltwater

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I was thinking to save on water and sewer costs I would put up a temporary tarp to collect rainwater directly from the sky (not off a roof or whatever) using a cheap $4 tarp (photo).

I only need 10-20 gallons per week, if it doesn't rain i'll use the rodi.  

 

So if I collect it and test it to 0 TDS or very close to it, I should be good right?

 

Thoughts?

 

 

bluetarp.jpeg

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I am not sure how clean rain water is. But my opinion is, you will be going through a lot to save a couple pennies.

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No, bad idea. Rainwater (by the time it reaches the ground again) is neither  distilled nor pure. It's condensed, but it will pick up particles and impurities that it encounters on its journey back to the ground.

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(These impurities will include nitrates and sulfates, as well as other stuff, that come from our burning fossil fuels.) (Relatable example: Acid rain.)

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Also, have you actually calculated how much money it costs you to make your water? I just looked up the water/sewer charges in Warrenton. If you use less than 2,000 gallons of water each month, and have a 1" meter, you pay 43.28/month no matter what (plus taxes/charges I suppose). If you use more than 2000 gallons, you pay $14.03 per thousand gallons. Assuming you use exactly 2000 gallons for your home, then how much extra does 20 gallons/week cost you? 4 weeks/month@ 20 gallons per week = 80 gallons. Assuming a 4:1 rejection ration, you throw out 4 gallons of waste water for every gallon you collect, so you actually use 400 gallons of water. $14.03/1000*400 = $5.61. (water cost). 

 

Noble idea, but as Tom said - the water isn't clean. Also looking at the cost breakdown, there are likely FAR better places to save costs than using rainwater for your tank (take a shorter shower for example). I also tend to take a more pragmatic approach when questions like this come up: If saving $6 is the tipping point to you having a reef tank, then the funds aren't there for a successful setup in the first place. I understand a few bucks in a few places can add up, but this isn't a place I'd skimp on - water is literally the life blood of our tanks.

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Bottom line... no. There are so many better options, and I'm betting even tap water is one, depending where you live.

What is rain? Water collected around dirt. So you'll have water with dirt that caused the rain. That rain will pick up more dirt, pollution (fertilizer, pesticides, smoke, car emissions, etc.), pollen, and whatever else is in the air. Have you seen how dirty cars are after it rains?

It sounds like you already had your mind made up and wanted kudos for the idea. We are all trying to tell you to reconsider.

You can buy RO water from a local store. You can buy distilled water from the grocery. You could use a Brita or fridge filter. You could use de-chlorinated tap water. Heck, some people just don't do water changes and are fine, so you'd just need top-off water if you were desperate.

But as previously mentioned... why chose this hobby if the basic costs of water are too much? You could get a used RODI unit for less than $100 including filters. You can recharge DI resin, but it takes a long time to recoup the supplies cost. A sediment and carbon filter is only about $13 and would last you quite a long time. Membranes are $25 and would last you years.

Please reconsider for the sake of the creatures in your care.



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ReefUp  you are getting a little aggressive with your feedback, might want to tone it down a bit.  I can afford whatever I want, whenever I want.   I have a RODI.  

I do not plan on putting it in.  So you are pretty much wrong on everything.  

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2 hours ago, PRinWarrenton said:

All good points. 

 

I'll collect a tiny bit in a glass and test with TDS meter out of curiosity.  

Cost would have to factor in replace rodi cartridges too.  

Operations cost certainly includes filter/cartridge replacement, yes.

 

Be sure that you realize that TDS meters measure electrical conductivity. What you're actually detecting/measuring is the presence of ions (charged molecules/ions) in the water. A good/common example of this would be salts (not just table salt, but salts in the chemistry -sense of the word). They don't detect suspended solids or dissolved, but not-ionized, solids or compounds (for example, suspended hydrocarbons). 

 

One other thing: The quality of rainwater will depend upon location, atmospheric conditions, the time of year, the weather preceeding it, and a whole lot of other stuff. It would be interesting to see if you could, from a data collection standpoint, track the variation in the data over time. I'd be interested in hearing what that data shows.

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Just thought of this: Sugar is another example of a solid that you can dissolve in distilled water that does not ionize when dissolved - that is, remains invisible to your TDS meter. You know it's there, but your instrument can't see it.

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Thanks.  That's why I post my thoughts before taking any action.  My tank has been really stable, less the stupid Toadstool masquerading as a rock for 10 days, so I wouldn't want to risk it.

 

Would Radon show up on a TDS?  We get letters from the water company a lot about it being in the water.

 

Probably will test one glass - if the tds is over 3, i'm done.

if = or under 3, may start drinking it.  I think that will make at least one person happy  LOL

Edited by PRinWarrenton

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3 hours ago, PRinWarrenton said:

Thanks.  That's why I post my thoughts before taking any action.  My tank has been really stable, less the stupid Toadstool masquerading as a rock for 10 days, so I wouldn't want to risk it.

 

Would Radon show up on a TDS?  We get letters from the water company a lot about it being in the water.

 

Probably will test one glass - if the tds is over 3, i'm done.

if = or under 3, may start drinking it.  I think that will make at least one person happy  LOL

No. Radon will not show up in TDS. It's an inert gas, also known as a "noble gas." It's not at all reactive and does not ionize under normal conditions (it's got a full outer electron shell and is quite happy keeping them all as-is. Thus, no ionizing without some pretty energetic input). 

 

If you go this route, it would be an experiment. You may not see effects immediately, but there may be undesirable long-term effects or even intermittent undesirable effects from variation in water quality. I've done experiments with my tank - many worked out fine; some not so much. In most all of those cases, though, I had some control over what I was doing. The variation that you could expect in the quality and impurity content of rainwater is something that you'll have no ability to really measure or control short of having access to some fairly sophisticated lab equipment. That's where, for me, it gets a little scary.

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4 minutes ago, Origami said:

No. Radon will not show up in TDS. It's an inert gas, also known as a "noble gas." It's not at all reactive and does not ionize under normal conditions (it's got a full outer electron shell and is quite happy keeping them all as-is. Thus, no ionizing without some pretty energetic input). 

  

If you go this route, it would be an experiment. You may not see effects immediately, but there may be undesirable long-term effects or even intermittent undesirable effects from variation in water quality. I've done experiments with my tank - many worked out fine; some not so much. In most all of those cases, though, I had some control over what I was doing. The variation that you could expect in the quality and impurity content of rainwater is something that you'll have no ability to really measure or control short of having access to some fairly sophisticated lab equipment. That's where, for me, it gets a little scary. 

Did you also have to make assumptions to the changes with temperature and weather (seasons)?

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7 hours ago, Origami said:

Operations cost certainly includes filter/cartridge replacement, yes.

 

Be sure that you realize that TDS meters measure electrical conductivity. What you're actually detecting/measuring is the presence of ions (charged molecules/ions) in the water. A good/common example of this would be salts (not just table salt, but salts in the chemistry -sense of the word). They don't detect suspended solids or dissolved, but not-ionized, solids or compounds (for example, suspended hydrocarbons). 

 

One other thing: The quality of rainwater will depend upon location, atmospheric conditions, the time of year, the weather preceeding it, and a whole lot of other stuff. It would be interesting to see if you could, from a data collection standpoint, track the variation in the data over time. I'd be interested in hearing what that data shows.

 

3 hours ago, littlelise1985 said:

Did you also have to make assumptions to the changes with temperature and weather (seasons)?

Yes. See earlier post. Assumptions won't do much good. They are variables, however. Changes in how the atmosphere stacks up; jet stream track; global volcanic activity (yes!) and dust storms; whether or not you're near an airport or a fossil-fuel burning power plant; ... you get the picture: The variables are nearly endless. Rain washes a lot of junk out of the air. Some of it is naturally present. Other stuff is created by human activity.

 

Sort of related: I read an article a while back about airborne bacteria serving as nucleation sites to form rain. Interested? Here's a story on it. I'll bet you weren't expecting fresh raindrops to harbor life, huh? :biggrin:

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I used to wonder if I could use the water from a dehumidifier as top off. I think it's kind of the same principles. It would take more energy to find a way to get it reef ready than would be worth it. 

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I used to wonder if I could use the water from a dehumidifier as top off. I think it's kind of the same principles. It would take more energy to find a way to get it reef ready than would be worth it. 
Ewwwww! I should take a photo of the inside of ours. That is some nasty water, and we're nonsmoker clean people that change hvac filters regularly. Blehhhhh. Terrifies me to think of that in our lungs.

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34 minutes ago, ReefdUp said:

Ewwwww! I should take a photo of the inside of ours. That is some nasty water, and we're nonsmoker clean people that change hvac filters regularly. Blehhhhh. Terrifies me to think of that in our lungs.
 

 

Everything kills you, it's just a matter of how fast! 

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12 minutes ago, YHSublime said:

Everything kills you, it's just a matter of how fast! 

Example: Saliva. But only if swallowed in small amounts over very long periods of time.  :lol2:

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3 hours ago, YHSublime said:

 

Everything kills you, it's just a matter of how fast! 

Seems true enough... my mom always say that the day you are born, you start to die (slowly)...

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7 hours ago, YHSublime said:

I used to wonder if I could use the water from a dehumidifier as top off. I think it's kind of the same principles. It would take more energy to find a way to get it reef ready than would be worth it. 

 

I tried this once for my reef, and used it in some humidifiers we had running in the house. Nearly instant algae bloom in the tank, and the humidifiers had more gunk and crusties build up in them than just using tap. I knew better, but was curious exactly what would happen.

 

It's like licking a metal pole in the winter up north - you know your tongue will stick, but you're just too curious not to try (yes, my tongue stuck - tried it once in 3rd grade. That S*^# hurts!)

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24 minutes ago, bues0022 said:

 

I tried this once for my reef, and used it in some humidifiers we had running in the house. Nearly instant algae bloom in the tank, and the humidifiers had more gunk and crusties build up in them than just using tap. I knew better, but was curious exactly what would happen.

 

It's like licking a metal pole in the winter up north - you know your tongue will stick, but you're just too curious not to try (yes, my tongue stuck - tried it once in 3rd grade. That S*^# hurts!)

Got a good laugh out of this one! Thanks.

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