A scuba cache is an underwater cache that is deep enough to require scuba gear and certification for recreational scuba diving. Scuba caches are not intended for everyone, and should have a terrain rating of 5 to reflect the specialized equipment and training required.
When seeking a scuba cache, be prepared and have all your gear in good condition, tested as necessary, properly packed, and ready to travel. You don't want to forfeit a scuba cache because you forgot to put your mask back in your bag before you put it in the car.
After finding the scuba cache, be sure to re-seal it carefully, so it remains water-tight.
When creating a scuba cache, indicate in your cache description any and all equipment and special certifications required for the dive. (Don't send a cache hunter into an underwater cave or wreck site looking for a cache if they are not certified for cave or wreck dives.)
The container must be durable, simple, and easy to open and re-seal. The more complicated the device, the less likely it is to maintain its water-tight integrity. Finding a scuba cache and getting it to the surface can be disappointing if it has been flooded due to faulty equipment or a negligent cacher.