Is it safe for the carpet shampooer to use a little borax w/reg. carpet cleaner?

Hopefully, they aren't fleas. If you can mix the borax with warm water before hand and make sure the crystals are completely dissolved maybe it will be okay. I'm afraid that it may clog the little valves and hoses and sprayers that shoots the water and cleaner through the carpet shampooer. I'd bathe the cats--yes, it's a lot of fun, they'll claw your arms and climb up your sleeves and clothes trying to get out of the water, but it can be done. Then I'd vacuum everything in sight more than once--rugs, the sofa, chairs, air out the ds or put them in the dryer for a bit if it's safe for the fabric, same with your bed comforters and pillows, wash your bedding. Do it on a regular basis.