Ive ran deca in the past when i was young
500 mg test / 400 mg deca
No hcg and no AI - poor diet as well, i grew and gained sized but i did have a lot of water retention (this was lack of knowledge around 6 years ago)

Im runing deca again now with a nice diet and an ai with good water intake and its going well.

If you run deca
Make sure your diet is very clean, your AI is in check and your water intake very high to help flush your body.

I think Test and Deca wil be a good third cycle for you