I'm currently on Tren/Test E as well and the below regimen prevent acne formation:
1) roccutane 10mg/d
2) clindamycin tab 100mg/day
3) Differin gel (night only)
4) hydrocortisone or betamethasone cream + gentamycin for big pustules
5) certirizine/ Zytrec one tab/day (to reduce inflammatory response)
6) 100mg lysozyme/danzene