What is your training experience, cycle experience, and body fat %? 20 to 25lb. of muscle from a single cycle is very unrealistic (unless your counting water weight gains you will lose post cycle). Deca is a long ester that will take weeks to peak, and I would run it at least 12 weeks. 500mg of deca split into two 250mg injections is fine. A gram of deca a week is pretty darn high though if that's what you intend. The same dosage advice goes for your sustanon as well (500mg per week, not 1g). I'd also suggest using enanthate are cypionate for your test rather than sustanon, as the latter has very long esters better suited to TRT.
My stats:28 years old 170lbs 5’11 I want to gain 20-25 lbs.
I need advice on a cycle of deca durabolin and sus 250.
My mate is looking in too doing a cycle as advised by his "body building mate"
He has advised the following:
Week 1-10, 500mg of Deca twice a week
And the same with sus week 1-10, 500mg of sus twice/week.