Filters causing bacteria?

[woodsplumber]

Should I change the cartridge filters on my RO daily to avoid bacteria buildup?

[JRCunningham]

I run permeate through mine every day at the end of the day until the concentrate line reads 0.0% sugar, then I know I've got the prefilter(s) cleaned out. I have had to replace both a cartridge and bag filter once this season due to some slime--but that was due to letting sap sit too long. If you've got the unit flushed out every day, your cartridge filter should be fine.

I am assuming (maybe incorrectly), that you are filtering the sap in some way before it gets to the RO. If it's raw and has bugs 'n stuff in it, all bets are off. One of the things I've done in the past is chart out what my normal concentrate flow rate is, and if it drops I know I've got a pressure/filter issue.

I hope that helps. Good luck.

--J.R.

[JRCunningham]

Also, if you've got a bug in your RO system, no amount of rinsing will get rid of it in my experience. The membrane is a great colonizer. You'll need to sanitize your RO (and everything your sap/sweet comes in contact with).

Dr. Tim has a great explanation here: http://mapletrader.com/community/showthread.php?9035-stringy-colloidal-part-syrup

Chlorine is a nasty thing for RO membranes, but my dealer had me put 1/2 cup of bleach into the prefilter housing (after changing cartridge filters) and run clean, soft water through until there was no more bleach smell in the concentrate line. It did the trick and I did several more batches with no sign of the slime. (I also had to sanitize EVERYTHING else in the shack). That said, do what your RO manufacturer tells you to do--I was really squeamish dumping bleach into a prefilter with a sticker right above it that said, "Warning! Chlorine will damage membranes". Nonetheless, I figured the manufacturer knew what they were doing.

Best of luck...