Using Mariculture-Deluxe-1.7.10-1.2.4.2, Forge 1355, game seems to crash every time I access a chest with a tank with Pressurized Water inside (the tank was placed in there before I updated to the latest Mariculture and Forge):
http://pastebin.com/wM1g25fX

Started a flatland world for further testing. Pressurized water in the world seemed to work without an issue (that I could tell), but it crashed the instant I tried to place a bucket of it inside a tank (this also prevents me from re-entering the world, producing the same crash):
http://pastebin.com/6Yj70F6D

Without Optifine, game still crashes (I don't think any other mod I'm using would break or modify its rendering inside a tank):
http://pastebin.com/f5YR0mMd

I attempted placing every liquid included in my pack in their own Mariculture Tank to see if it affected any other liquid other than Pressurized Water, but it seems that it is the only liquid with this issue.

Yeah it wouldn't be optifine. I'd noticed pressurised water always acted strangely compared to my other fluids before as well. I guess it's just screwed even more with the rendering of fluids in tanks. Going to release a with a quickfix for this.