In the first place, there is no way you are going to put on 25 lbs. of muscle with Deca. It is well known to be a slow gainer. There is no way you can put on 25 lbs. of muscle in a short time with any steroid. It is mostly water gain and the more androgenic a steroid is the more water gain you will get. Anadrol is famous for this. In the Oct.,2009 issue of Mus. Dev. mag., Anadrol was featured in an article by Seth Roberts. Quote: "Anadrol has a reputation for dramatic size and strength gains, however it is well known that these gains tend to disappear once the drug is discontinued." " This is likely due to a large degree of water retention brought on through inhibition of 11-beta hydroxylase, which would explain the bloating and high blood pressure that most people report while being on this drug."
In the Sept.,2010 issue of Mus. Dev. Mag. , nandrolone is also profiled by Seth Roberts. There is no mention of nandrolone causing water retention. He says " The major drawbacks to nandrolone are its reduced androgenic activity and it is a potent stimulator of red blood cell production."
That describes my experience with nandrolone in a number of cycles over the past 6 years. I have never experienced any water retention and only lose a couple of lbs. back.
There are some people who don't respond well to anabolic steroids and should never take them in the first place.