When to Start PCT?

[reddragon4954]

I am thinking of doing a cycle w/ Sust. 250 which will have the longest ester of the stuff I'll be running it with.

When do I start the PCT? I know that Sust. stays in the system for 3 weeks but I have heard from others to start PCT on the second week after last shot, what is correct?

[x_moe]

18 days after your last shot
http://forums.steroid.com/showthread.php?t=94822