Unfortunately, I was unable to get permission to use this mod in my modpack due to complete lack of response from the creator.
Fortunately the Just Another Spawner Mod was able to give me the same gameplay with the proper configuration. Additionally it has the side benefit of making squid spawn less out of control.
I'm glad you found another mod that worked for you! I'm very sorry for the lack of response. I have not been involved in Minecraft modding for a while and didn't get the message until today, when I logged back in after years.
Better late than never... I've now given open permission in the OP.
Done! I am unlikely to continue work on this any time soon, so I am happy to put it up on GitHub. I should have done this years ago, but at least now it's out there and under an open license. See the edited OP for the link to the source.
It's a pretty simple mod at version 0.1, and the code is only a couple screens' worth. Have fun!