ditttohead
Water systems designer, R&D
Is that 2400 gals what is reset on the contrrol at the end of a regeernation or is the figure higher between regenerations? IMO unless you have a large family, and if you do, a 1/5 cuft is probably too small because 2400 gals sounds way too many and would mean you are regenerating only every few weeks but...
Is the brown water happening right after the regeneration at 2AM that morning?
What is your programing for the softener; what gpg of hardness and di you add in for the iron and manganese, what K of capacity, how many people, how many lbs of salt, how many gallons between regenerations?
I agree with Gary on this one. If you are using your softener for any iron removal, a frequent regeneration should be done. I would also recommend not doing a low salting either, in order to remove the iron from resin, a lot more salt is required.
You can try a few simple ideas. Use a res-up feeder, this is simple, cheap, and fairly effective. Order the double backwash cam for the 5600sxt, and program the valve for double backwash, set the second backwash and the final rinse for 10 minutes each. This will use more water, but will keep the resin cleaner. Or, just program your valve as it is now with a longer backwash, and longer fast rinse time to see if this lessens the problem.
http://www.freshwatersystems.com/p-6168-res-up-liquid-resin-cleaner-feeder.aspx