868 Mhz Antenna partially under water

Hello, hopefully i´ll find here a real antenna expert.
I have a boat which I want to upgrade with a 868Mhz Data Link. Because of a special closed hull the 17cm Antenna has to go under deck. But that means that 2/3 of that antenna is above sea level, 1/3 is below. Can someone tell me if that works at all? Or just a bit worse then optimal? Or doesnt it matter at all? I would like to install the antenna straight upright.
Thanks for any advice!

Hi Denis - submerging an antenna in water decreases the signal strength considerably - the higher the frequency the higher the absorption of signal strength - a partially submerged antenna is probaly kind of “to short” for 833 MHz - things become worse in chlorinated pool water - and seawater is generally a no go - Theo

HI Theo,
thanks for your reply! Just yesterday I did a test and it worked quite well! Even with the base station right on the ground. But I have to say that I´m using a long range radio and have to cover an area of just about 100x100m. My biggest concern was, that it wouldnt work at all, …but good news!