Wierd Idea???

[yukonblizzard]

I am not sure if this even makes any sense but could you put a Reverse Osmosis conected to a tank were it would clean a few gallons of the water a day or would the salt water destroy the filters?? Or would this not even do any thing like take out ammonia and nitrites and nitrates???

The reason I ask was I have to perform a lot of water changes and I was thinking if this would cut down on the changes.

Any thoughts would be appreciated.

 

[Zaita]

It'd strip the salt from the water. You'd end up with pure-clean fresh water.

 

[yukonblizzard]

Yeah, I kinda figured that, but thought it might be an interesting project. But if the salt is trapped in the filter and water flows through it wont it cary the salt with it or is the filter so small that this will not happen.

Also if it does take out the nitrates and ammonia could you use old saltwater from a water change and run it through a RO it could be reusable???

Thanks for the reply.

 

[ReefEnabler]

sounds like you are talking more about 'dialysis' which is where you use a membrane to separate two liquids. On one side of the membrane a liquid with all the desired chemistry is passed. on the other side is your 'undesired chemistry'. Osmosis will have all the pollutants pulled from one side to the other, and all trace elements lost from the 'undesired' side will be replaced from the other side.


The only product on the market I know that is set up to do this with saltwater is "dialyseas". Google it up, very interesting but very expensive.

Of course this only works if the 'clean' liquid on one side of the membrane is constantly replenished, otherwise both liquids would come to equilibrium with undesirable stuff still in the water. I'm honestly not sure how the dialyseas handles this....

Ive spoken to people who use the Dialyseas. yes its basically the same hardware that somebody would use for dialysis with kidney problems, crazy eh?

 

[ReefEnabler]

"But if the salt is trapped in the filter and water flows through it wont it cary the salt with it or is the filter so small that this will not happen."

It seems you slightly misunderstand how reverse osmosis for pure water works. Most of the water passes straight through the center directly to WASTE. This is the path of least resistance. The system works because you RESTRICT the waste line, which creates enough backpressure so that some of the water passes THROUGH the membrane. Nothing but water will make it through. Everything else gets flushed out the waste, which is the easiest path through the membrane.

Re: reusing saltwater...

you could in theory process your old saltwater, but it would be a bad idea IMO. The TDS content of the water is what determines how well the RO works. I'd be willing to bet that saltwater will exhaust an RO membrane much faster than tap water.

everything below this line is more speculation than anything since I cant recall the facts entirely.....
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I have read somewhere that DeIonization does NOT remove salt from water, and that it could be used to filter saltwater. I am not sure what the benefits of doing that would be though, and it seems expensive/wasteful (but I am lacking information). If anybody has information on this I'd be interested in hearing it.

 

[yukonblizzard]

Ohh Ok,

Your right i dont know much about Ro

THanks

 

[ReefEnabler]

its a good question and a good thread, I am currently trying to remember where I read about that DI used to filter SW....

I believe it was from a vendor website that sold bulk-DI-resins. I call it having a black background and tons of resins to choose from, and a paragraph at the top talking about how certain ones can actually be run on saltwater.....

ok maybe I am crazy but I am trying to find it........

 

[yukonblizzard]

Thanks for the help and suggestions

 

[ReefEnabler]

Ok I believe I found what I was referencing earlier...

from The Filter Guys DI resin page:
"Beside totally purifying tap/well water before using in an aquarium, the combined KATI and ANI system can be used to temporarily to reduce the total mineral content (including Nitrate) in a saltwater system, thereby reducing the need for water changes."

http://www.thefilterguys.biz/kati_ani_di-onizer.htm

I think it might be possible, but you will probably burn through DI resin pretty quick, so I doubt its efficient long term.

I am also not sure if this is specific to separate cation/anion DI resins, or if typical mixed bed resins cartridges would also work.


here's an idea...
next time you are throwing out your "Bad" DI resin because your RODI water is approaching >5ppm, hook that DI resin up to your system for a day and test nitrates before and after. Can't hurt.... Small pump like a minijet 404 or some kinda maxijet would be perfect.

I'd also recommend keeping an eye on salinity just in case.

 

[yukonblizzard]

Good idea, I think I might try that

THanks