Bug report: the iron tanks don't use the color multiplier both in world and in the GUI.
Proof: http://imgur.com/a/jdG46#0 (the ender tanks and the translocators are there to show what it should look like)
The liquid is Tea from the Avatar mod, source can be found at https://github.com/KeplerGaming/Avatar-the-legend-of-Steve. If it's a derp on my side or I'm wrong please tell me. All the mod versions used are in the description of the album.

Another thing that I'm wondering is and not sure if it's normal or a bug is that the tooltips of the liquids are like fluid.tea and normally I would assume it's our side but it happens with water too and the liquid nodes from Extra Utilities show it as Tea as you can see from the album.

Localization is your issue, I simply use the return value from Fluid.getLocalizedName() or whatever the function is.

Localization is now fixed by https://github.com/KeplerGaming/Avatar-the-legend-of-Steve/commit/78765b9583b5948a543bbf10bc570d0af3900ce3, but the fluid in the tank is still just gray.