Contaminated Salt Water Storage Question

[saltwaterwannabe]

I moved a different pump to my salt water storage tank and saw a lot of junk growing and floating in the tank.  I have never had stuff grow in my storage tank before and my RODI tank is still clean as a whistle.  I cleaned the container well and am ordering new filters as a precaution although my TDS still shows very little getting by the filters.  I changed to Reef Salt a few months ago, but I sure did not think it would grow stuff in the storage tank.  Any ideas what would be causing this?

 

[bcavalli]

If your using a naturally mined salt it will leave dust particles or residue in your mixing barrel.  I switched to SeaChems Vibrant for that exact reason.

 

[saltwaterwannabe]

Looks like my tds meter is off since my resin is now dead.  About a month ago I replaced my sediment, 2 carbon, and 2 di resins, making sure to flush before running water through the di resin.  My membrane is 5 months old.  Both my di resin cartridges were toast after around 100 gallons of water, which is nuts.  I believe my membrane is shot again as well.  I have gone through 4 membranes in the past year and a half, so I must be doing something wrong.  I flush the membrane with a valve for 15 minutes before and after making rodi water, which did make this filter last 5 months but is not nearly long enough.

I ordered the following and plan to upgrade my filter system: booster pump with auto flush, 2 new 100 gpd membranes, 1 membrane housing, 1 chloramine filter, 1 carbon filter, 1 sediment filter

The water runs through the following path:

valve

tds 1

sediment

tds 2

5 micron carbon

.5 micron carbon

tds 3

membrane

tds 4

3 way valve to bypass di resin for flushing new filters

di 1

di 2

tds 5

I already have a pressure gauge and a manual flush valve.  I removed the restrictor when I added the manual flush valve as per instructions.   I replace the sediment filter every 2 months, carbon every 3 months, and the di when one entire cartridge has changed color.

I must be overlooking some obvious flaw in how my setup runs to be going through so many membranes.   I would rather not burn through two brand new membranes so your input is greatly appreciated before I hook it all up.  Any idea what I am missing or doing wrong?