DI resin question

[reefkeeper2]

The water in my town is high in phosphorous. I have a R/O DI unit that removes almost all of it, but I can still detect a trace amount using a salifert test kit. To eliminate this, I added on another canister with anion resin in it. Imagine my surprise to find that the reading on my TDS meter is higher for the water coming out of the new canister than the water going in. I am using one of those in line TDS meters. To check it, I swapped the probes and got the same reading. Can anyone explain this?

[Billybeau1]

How much water have you run through it so far. New filters need to initialy get flush out. About 10 gallons or so if I remember correctly. Make about 10 or 15 gallons of new water then check the tds.

[reefkeeper2]

Its been operating for about a month now

[Billybeau1]

hmmm. Let me see if I can get you a little more help.

[AZDesertRat]

You might try asking this question over in the Spectrapure Vendors Forum. I know they have a couple different cartridges designed with phosphates in mind. One thing they do recommend is put the anion cartridge ahead of the mixed bed or cation for some reason or another which maybe they can explain .
They have a new product on the market called the MaxCap DI system that uses a proprietary cartridge that when used ahead of a mixed bed DI will extend the DI life by at least 3.5x and give you 18 megaohm water. I am testing one now with a Thornton resistivity meter and so far its perfect. It will take me quite a while to exhaust it but I have made 90 gallons of 18.2 megaohm water so far with no hiccups.

[Billybeau1]

Thanks Rat :thumbsup:

[Roland Jacques]

isn't their also a shelf life on resins?

[AZDesertRat]

If its not kept wet and sealed, yes. Seal a Meal vacuum sealers do a great job of sealing bags of resin for longer life.

[reefkeeper2]

Thanks guys, I got my answer on the spectrapure forum. :)

[Billybeau1]

:thumbsup: Stop by any time :)