Bacterial infection of Coolant
I've just cleaned out the sump of a mill machine of around 10 gallons of coolant. Should I be worried about bacterial infection?
The only reason I'm asking is that the coolant had been lying in there for about 5 years and I noticed some kit in a nearby drawer which are basicaly culture slides to test for bacteria that you're meant to incubate for 24 hours at 30 deg C for 48 hours.
Once I get it clean (hopefuly in the next hour) I'll stick an aerating pump in the sump so that the anerobic thingies dun multiply, but how concerned should I be about this? is it a real health hazard or just crap?
How often should I be changing the coolant totaly please?
The testing things, if it helps, mentions Bacteria, Yeast and Fungis and has a 5 scale comparison for Slight, Moderate and Heavy infection.
Oh, the machine was left in this state by my predecessor and I wasn't too worried about coolant since I mostly machine plastics and ally, but I got this stainless job to do now and I assume I need coolant cos everyone says you do.
I love deadlines- I like the whooshing sound they make as they fly by.