My first shaders experience

Just downloaded shaders for Minecraft for the first time. I also installed Optifine and some mods to my Minecraft client to make it work better and to help reduce FPS drops that would came as result of shaders use.

There are some things that don’t make much sense tho. For example can I combine multiple shaders? I wasn’t able to find that option in settings.

Also in some cases colors are off by a lot, like for example everything is too yellow, when you’re mining it never gets dark and so on. The water is strange to especially if you’re looking in it.

Could it just be bad shaders pack or am I doing something wrong?