Old tank water

What I currently do is use the old tank water from the reef tank and use it for a fowlr tank. Fish do fine in less than perfect water. From the fowlr it goes down the drain.
 
My RO waste water goes down the washing machine drain. My water change water goes down the toilet. It all makes it back to the ocean eventually anyways. Water is like matter in the fact that it can never be created or destroyed, wait water is matter...ok i'm getting off topic here.
 
Mine goes down the drain. My local wastewater treatment plant (the biggest in the state) processes about 200 million gallons of water every day. (It's permitted for 230 mgd, and will probably expand again when more people move to Phoenix.) Next to 200 million gallons a day, my 8 gallons a week is insignificant.

Re-use is a good philosophy, but if you're looking for an area where your individual action can make a big environmental impact, what you choose to do with "old" tank water is probably not it.

Note: If you live on the coast and dump Caulerpa or its spores into a body of water where they don't currently exist, you can make an impact - a bad one. Come to think of it, a trip through a WWTP equipped with chlorine or UV is probably a good thing for old tank water in any coastal area.

Here in Phoenix, it takes a very patient definition of "eventually" for water to get back to the ocean. The path involves evaporation, cloud formation and coastal rain, or seepage through an aquifer. It certainly doesn't get there straight out of the wastewater treatment plant, that's for sure.
 
I have wondered how my saltwater changes would affect my ceptic tank. Anybody have any info on that?
That's a valid concern. Adding a few gallons per week of salt water to a 1000 gallon septic tank has a lot more potential to mess things up than adding the same amount of salt water to a municipal WWTP.

First off, your pipes might corrode faster, if they're metal. Second, the salt water might not be real good for the bacteria that live in your septic tank. Third, the tank itself or your leach lines might corrode, again if they're metal. Lastly, you could have the same kind of salt poisoning that was discussed earlier re: dumping salt water in the back yard.

Most septic tanks lead to a shallow leach field under the yard. In many cases, grass has no problem pushing roots deep enough to suck up the water in the leach field. If the leach lines are adding too much salt to the back yard, you might start seeing brown, dead grass where you used to have your greenest grass.

On the other hand, if your leach field is deep, or your household uses lots of water, or water moves through your soil very quickly, you might not have any problems.

Here's an article on water softener brine and septic tanks, a somewhat-related issue.

This issue has come up several times before on RC, too.
 
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All of my piping is PVC so thats not a problem. But I have wondered if it would affect the grass above the leach field. On average I change 20-25 gallons every 2-3 weeks. So, max water would be 50 gallons a month.

Cant do the driveway, it'll just end up running in my yard.
 
All of my piping is PVC so thats not a problem. But I have wondered if it would affect the grass above the leach field. On average I change 20-25 gallons every 2-3 weeks. So, max water would be 50 gallons a month.

Cant do the driveway, it'll just end up running in my yard.
Could you empty it into a tupperware tub, let evaporate out doors? Then just scrape out and throw away the residue. Just a thought.
 
Evaporation is definitely an option, if you have enough space. Climate will definitely make a difference in the required size, though. In a hot, arid climate you might need X square feet to evaporate Y gallons per day of salt water. In a cool, humid climate, that X variable will be much, much larger. A shallow, wide basin drys faster than a narrow, deep basin, but it also takes up more yard space. Add rainwater to the equation, and it may be difficult to maintain a large enough evaporation basin in your yard.

You could try an experiment with a kiddie pool. Put the waste from your next water change in it, and keep track of the days it takes to dry.
 
Yeah I do pour some in the front yard lawn, some in the back yard lawn, some with the shrubs, some in the outside plants. But not very often. most of it goes down the drain to the septic until landlord decides to hook up to sewer. Since i dont think septics tanks do much to old aquarium salt water, I figure it's just as bad putting it on the grass as it would be coming out of the leach lines inches below.

Nonetheless, a question I've been wondering about. Maybe something in the future where like we do for oil today... we would have to take it back to the LFS or some other recycling store or better yet an energy plant. they can take the waste heat to boil off the water and leave a very concentrated brine solution more economical for transport for recycling into say new salt? I know we did this onboard my ship to make fresh water from seawater. But the brine just went back overboard.
 
You could put it down the drain but it is easier to pour in on the lawn. No aiming or missing and the wife getting mad ablout the mess.
 
I put mine down drain or down driveway. Septic systems maybe..maybe could be affected. Depends on septic system as to if it would affect or not. All septic systems are set up diffeerently. Most older systems are 1000g single compartment and gravity feed to leach field. New systems can be very complex and any biomass other than human waste can cause problems. You would now pretty quickly if it is causing problems, if grass is dead or if there is a stench in the air....you have a problem. Most of the grinders/dosing pumps used in septic tanks all are made of stainless connected to pvc so should not have any corrosion problems.
 
I put a little in my girlfriends cichlid tank in hopes it will one day kill them so I don't have to deal with that nasty freshwater any longer :love2:

Honestly it goes in the toilet.
 
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