The Salty Side: Saltwater Aquariums for Beginners

Ways to Re-Use Waste Water from a RO/DI Unit

Most of us try and conserve and recycle as much as possible.  Sadly, our planet needs all the help it can get.  One way of doing this is to reuse the RO/DI Unit waste water that would otherwise go down the drain. 

It obviously depends on where your RO/DI unit is situated but waste water could be collected directly in a bucket or large container.  This could then be used in any of the ways listed below.

Some simple ways in which to reuse RO/DI waste water are:

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You can run your waste pipe directly into the drum of your washing machine before the start of the first cycle.  This is probably easier than emptying the water from a bucket.  Unless of course, you have a top loading washing machine. 

Watering the Garden

This is more beneficial in summer and especially in warmer climates where there is excess evaporation.  Water could be filled directly into a rainwater tank, barrel or bucket and emptied straight onto lawns or plant beds.

Watering Houseplants

This would require emptying the waste water directly into a bucket or watering can and then using this to water house plants.

Top Up a Pool

I would only use this if it were a large pool and not the small inflatable types.  In areas with hot climates and a large amount of evaporation occurring, this would be ideal. 

Filling Toilet Cistern

By using a stop valve you can turn off the water from the main water supply to your toilet and fill the cistern with water from the RO/DI unit.  This can be done with a bucket but if your RODI unit is near enough to your toilet, this could be plumbed in and regulated with the stop valve. 

So there you have it!

Waste not, want not … as the saying goes.  Hopefully these ideas have been helpful if you’re wondering what to do with all that waste water coming from your RO/DI Unit every time you run water for your saltwater aquarium.

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