It's probably ignoring the colour values returned by Fluid.getColour(FluidStack)

what fluid is that?

Oh and it looks like the filter interface also ignores the colour AND the localised name returned by FluidStack.getLocalizedName()

(apple fluid is just a debug fluid I made so I could test some stuff =P)

@HenryLoenwind A generic fluid added by AOBD.
It uses a default white texture tinted with the colour of the specific metal it represents. You can see the src code for it here

yeah, that would be missing from everywhere we render fluids. I never heard about applying color in addition to the texture for fluids.

Never? That's quite surprising to me XD
It's the standard on how to render a fluid. As you can see by the Tinkers tank in the first picture.
Railcraft, BuildCraft, ThermalExpansion also all apply colours to the fluids they are rendering in their respective tanks.

and the getLocalizedName() is called on the fluid, not a fluidStack...because the filter only stores fluid, not stacks. I need to look into this one deeper.

You should probably store the FluidStack since NBT data might play a part when filtering fluids
Edit: You could also create a simple dummy FluidStack so you can call the appropriate getLocalizedName()

I'm pretty sure any fluid with nbt would not be happy in any eio tank or conduit...

We only have fluids, everywhere. when comparing inputs and outputs, in our tanks, ...

Well lucky for you guys NBT data is not often used with FluidStacks, but in some cases you could probably cause some exploits/loss if you're not storing the NBT data of anything.

Ok, I'll handle it. That will be a major overhaul of every single bit of code that touches fluid. As such I put this on hold for now, as we are in the stabilization phase for release 2.3.