BIRM - How To Replace / Use in Filter Tank
Last Updated: 01/14/2015
BIRM is primarily used for reduction of iron that is oxidized..
Requires high flow rate for back washing ( heavy media )
Requires frequent back washing ( to remove oxidized sediments )
Normally you would use a 9" or 10" diameter tank ( 9 x 48 = 1 cu.ft. BIRM with 13 lbs. gravel, or 10 x 54 tank holds 1.5 cu.ft. BIRM and 16 lbs. gravel )
9" tanks should be backwashed at 5 gpm, and the 10" tanks at 7 gpm.
Failure to "properly" backwash this media results in "fouling" or "clogging" of the media.
And it can "collect" oxidize iron in the tank... resulting in "bad" water after each backwash ( because the backwash flow rate was too low or not frequent enough ).
There is no "equation" for how often to backwash a BIRM tank.
But here are some "recommendations" for operation based on the IRON level in PPM and the amount of water used ( gallons or number of people in the house ).
And the more you Backwash the better.
Common is every 2nd night... assumes 3 - 5 people and IRON between 4 - 10 ppm.
If more people, or more iron, you need to Backwash every night to keep the oxidized solids out of the tank ( prevent clogging or "Fouling" from too much oxidized Iron remaining in the Birm Tank ).
If less people or less iron, you could reduce to every 3rd day ( night at 12 midnight ), but if water is used a daily bases, I would not backwash any less than every 3rd night.
And the larger 1.5 cu.ft. ( 10 x 54 tank ) should be used if iron level is above 5 ppm. AND a water softener should be installed AFTER the BIRM filter tank to remove any iron not "oxidized" from the water.
We can sell you the mediato re-bed your current system ( plus you would need some Gravel too, based on tank diameter - 13 - 16 lbs. ).
Most wells don't have enough flow from the well / pump to backwash more than 1/2 cu.ft. of this media ( properly backwash ), and there are other ways to handle Iron and Hydrogen Sulfide.
We would need to know the water analysis of your water source ( hardness, iron in ppm, hydrogen sulfide in ppm, and pH ) before we could make any other "equipment" or "media" recommendations.
To REPLACE the Media in the Tank
1. Turn off water, unplug control valve from electric outlet, disconnect control valve from water lines, and drain line.
2. Unscrew control valve ( may require two people ) from Tank.
3. Remove control valve and distributor tube ( the two normally can be separated at the control valve, as the pipe is only connected to the valve by an o-ring ).
********** EMPTYING the TANK
4. Now the fun part. Depending on your situation ( size and location of your tank ), you need to either dump the water and Media ( BIRM, and gravel ) out OR use suction to remove them ( shop vac, or other means ).
5. You can clean the inside of the tank with chlorine ( bleach ) if you feel it needs it. If you need to scrub the inside of the tank, use a clean toilet bowl brush with piece of pipe to extend the handle.
******** REFILL with NEW Media.
6. a. The next step is to replace the center distributor pipe into tank.
6. b. Then you pour a 4-6 inch layer of fine gravel ( 1/8" x 1/4" ) into the tank. Remember, you MUST have the distributor tube in the tank before you start filling with gravel.
**** Be sure you cover the top opening of your distributor tube to prevent any gravel from getting inside. A plastic sandwich bag and rubber band works well.
7. Now do steps 3,2,1 in reverse ( put valve back on tank, screw on by hand, and reconnect pipes and power ).
8. Once reassembled you should backwash for 10 minutes using your control valve ( All control valves have some way to manually advance the valve to backwash ). You can allow the valve to run a complete regeneration cycle, but it is not needed. You are just "cleaning" or "rinsing" the "dust" off the new media.
9. With the control valve in the normal "service" position, run the water in the home for a few minutes to clear the lines of any "trapped" air or debris loosened during your repair.
10. - You're Done -
For Water Softeners, see RESIN Replacement Guide