The current combination you have is pretty common among T5 users.
My experence with T5s overdriven on Icecap was not very good, I used them for about 1 year. I just recently took them off and no longer use T5s particularly for LPS as my previous experences with VHO, I found the VHOs to perform better.
One of the things that others recommended to me as to why they didn't perform well was because I wasn't using a variety of bulbs. I was only using the Aquablues. I hated the fake blue of the Blue+ so I used
VHO actinics. The 65K daylights were just too yellow. So really for my preference the only bulb I liked aethetically was the Aquablue as since that didn't work out, I scrapped them altogether for LPS/Softy dominate tank.
Perhaps Fritz ( HFG ) can give you some advice.
