How often do you all clean out your tank ? Do you recycle your garnet? Just curious

Cleaning out the tank depends on two factors...

1) The size of the tank
2) How often you use your machine

For most users, about once every 6 months seems to be about the norm.  Obviously if you have a small 4 ft x 4 ft tank and run 20 hours per day, it will be much more frequent.

Do you mean how often do we empty the water tank under the slats?  About once a year or so.  We use three Flow machines with an E-ductor system (don't know... google it) that draws used garnet from the bottom of the tank and deposits it in a hopper next to the machine.  They require regular maintenance to keep from clogging, and the pump that drives them needs to be replaced/rebuilt about every six months or so, 'cause the garnet chews it up pretty bad.   Then again, we're running these machines pretty much 24 hours a day, 5 days a week.   We dump the hoppers at least once a week, in a huge pile outside.  From what I understand, some concrete company takes it off our hands occasionally.  I assume they mix it into cement or concrete or whatever.  I don't know if we pay them to take it, or they buy it from us, or if money exchanges hands at all.
When we DO empty the tank, it's a huge pain in the butt.  Lots of slat scraps, and stainless steel drops from the stainless material we cut.

again, it all depends on how often you use your machine. that e-ductor system sounds cool, but i dont think id want it in my specific application. maximum on the machine is about 8 hours cutting time per day. but we have a septic company come out and suck out the abrasive about every 350 pump hours. just figure your abrasive flow rate to your pump hours and youll have a decent guess on how much is down there. just my 2 cents. ive heard of companies that make their employees SHOVEL it out! glad my boss likes me... ha ha

we also use the big sucker truck to clean it out. It seems like it would be costly but consider how much it costs to run one of those aftermarket recyclers. they use a lot of power to dry that wet sludge.

We have a guy that likes to shovel it out . LMAO. He gets to do it once a month.

Im one of those that have to use a shovel, let me tell u that is hard, dirty, smelly work. Im trying to convince my boss to get a pump to suck it all out but tht costs to much apparently.

No doubt, it is a pain the butt.  If your going to buy a pump, use a Zoeller with bronze impellers and throw it in the bottom of the tank.  Its a few hundred bucks, but will save your back.