Not quite. Anti-freeze is the undiluted liquid that you mix with water (usually 50:50). The proper term for the mixture is "Coolant". I would say that "coolant" and "radiator fluid" are synonymous.
Antifreeze
antifreeze is usually mixed 50 / 50 with preferably distilled water for your cooling system ( up to 60 % antifreeze if colder climate ) which includes the radiator , heater core , radiator hoses , heater hoses etc.
radiator antifreeze coolant.
the cooling tank in the radiator for the transmission is bad
You have a failed radiator. Most vehicles have a trans cooler on the side of the radiator.
The transmission cooler (possibly part of the radiator) has failed
Same color as what?
Most transmissions are cooled using separate tubs in your radiator, if this tube develops a leak it could mix with your antifreeze, you need a new radiator...
You have a leaking transmission cooler, usually part of the radiator. The transmission fluid is mixing with the antifreeze turning it pink.
Antifreeze is green in color and is leaking from your radiator .
To change the antifreeze on a Mercedes, locate the drain plug on the bottom of the radiator. Drain the fluid into a pan and refill it.
Most Likely you have a leak from the transmission cooling tank on your radiator to the antifreeze portion of the radiator. Jeff