Yep, us fishermen have a lot of responsibility with our spinning reels as well, when I was fishing the surf down in Marco Island and Naples, I was both rinsing my spinning reel underneath the sink and also dipping it in the tub for 5 minutes. Then after 2 weeks or so, oiling it back up.
I think you have to do the same with the Underwater Drones. I put my
Chasing M2 in a bath tub even after using it at freshwater lakes in Michigan to get all the weeds, sand, and gravel out of the motors. I'll move it around using my controller, blasting the thrusters, trying to get all that stuff out of there for a good 10-20 minutes. Saltwater you'd probably have to do 20 minutes.
Every so often I'll use
Liquid Wrench Silicone Spray on the motors to prevent them from locking up, keep the motors running smoothly. Have to be careful which silicone spray you buy, I know many other
Gladius Mini owners use the
Q8 silicone spray. The Liquid Wrench Brand I use does say it's safe for rubber and plastic. Some drone hobbyists have said first try it out on another piece of plastic first just to make sure if you use a different brand.
Also if your
motors are locked up, some Gladius Mini owners have used
WD40 and a wrench to unlock them, WD40 is not something you should use all the time though like the silicone spray, underwater drone hobbyists just did this specifically to unlock the motors that is it.