[forbze16]

Lets see if I can make sense of this.

I want to take a Aquarium Pharm. TWP unit, empty it of exhausted media, fill it with poly-fiber and carbon and attach that in front of a new TWP unit in line.

Has anyone tried this? Will it make the DI unit last longer?

RO isn't an option because waste water in drought restrictions isn't cool. And I'm not motivated to reuse some 40 galons a week of waste water. I heard DI is better than just straight RO anyway.

Thanks in advance,

Dave

[AquaFx]

The only way you can extend the life of DI resin is by feeding it water with lower ion content.

The way DI works is ion exchange. So all the "filtering" in the world will not lower the TDS. I know waste water stinks...have you looked at permeate pumps? They cut waste water by up to 80%

Just a thought

Marianne

[forbze16]

Marianne,

Thanks for the reply. I actually had this posted on RC too and the guys from Aquaticreefsystems.com tracked me down and gave me a great deal on an RO system that I can connect to the TWP. Worked out in the end.

Not to preach, but if you are interested in a RO/DI system I recommend at least talking to them. They were extremely helpful and gave me a good deal.

Dave

[AquaFx]

Dave,

I guess I did not understand. You said an RO was not an option.

Just changed your mind? That cool, RO is an excellent way to feed DI.

Also you might want to use a permeate pump, you need a pressure tank to do that. If you do use one, you can cut waste up to 80%. That might make you happier. It is non-electric and a great invention.

[forbze16]

Actually I did sort of. You didn't misunderstand.

The waste water is a big factor. But with the flow restrictor I can reduce the waste to a 1.5:1 ratio and that is acceptable. The 4-5:1 wasn't, and all the posts and things people were saying it seemed to rule it out. After talking to the guys at Aquatic it seemed my percetions were worng.

At the lower rate I can find stuff for the water, dishes, lawn, plants etc.

And we shall see if it lives up to what they say it can do. Nothing wrong with a little scepticism.

Thanks again,

Dave

[AquaFx]

Be aware that reducing your waste water in that manor (increasing back pressure) will shorten the life of your membrane.

There are parts of the world where water is in such short supply that replacing the membrane every 6 months to 1 year is worth the water savings.

If you operate the membrane at the manufactures specs...see www.dow.com ....your membrane should give 3 or more years.

Now if you have high silt or you over heat it, you will not get three years. But normal operating condistions you will get three years or more.

Good Luck

[forbze16]

Thanks for the tip and the link.

As I understand it- the membrane will be reduced to about a year, maybe a little more.

Now to save up for the 90 and really start rocking.

Thanks,

Dave