Thirty foot depths have been possible because of people with test tanks at their companies. They used the transmitter off to the side so range was not an issue.

Use GE Silicone II RTV on your hoses..all the way around them and you won't have any problem with water in the hoses. You need to do that with motors and the receiver also on all seams...all around. If your going below 20 feet, you need to pull the hoses off and silicone on the INSIDE of the hoses also.

Below 20 feet or so most have said bye, bye to their walley sub as hoses began to pop off and seals burst....