Updated to 1.14.x
With the recent ocean update I recommend you actually tweak the value of fog to a value that is a little bit over 0 instead. That way it would still look like you're under water.
I liked how it looked at 0.0075 for water fog.
edit: I made a mistake in the config text. Vanilla's default value for water is 0.05, not 0.1
Fix console spam.
Add a config file
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Turn off water/lava fog removal
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Adjust fog density (Default 0 for water. Check the config file for some more explanation.)