Rusty coolant/block sealer?

[gregorys1989]

Is there a way before flushing my coolant i can tell if the rusty looking coolant in my radiator and resivour is loaded with radiator stop leak/block sealer?

 

[locovaca]

Look at your radiator cap. 3:40 in this video: http://www.youtube.com/watch?v=76GpMD4LIwY