The pro0blems with red or long life coolant start with running low on coolant and letting air into the system. A bad radiator cap is the most common cause for this. Flushing and refilling with the long life coolant (notice I didn't say Toyota red) is what's supposed to happen. If you have green coolant in your system, you are headed for trouble. Some misguided souls believe all long life coolant is bad. They are wrong. But they often do a drain and fill or top off with "regular" coolant. If you do have green in your system, you need to have a COMPLETE flush done with a machine to get all remnants of the mixture out of the vehicle, then a fill of good quality long life coolant.
Long life coolant is almost clear, to orange to red. It is not green. Long life coolant uses a completely different set of additives and modifiers that do not play well with the additive package in green coolant.