Hayward Astrolite Series Underwater Light

I believe the light we have is the Hayward Astrolite.  We replaced the standard bulb with an LES several years ago, think it was a 20w LED, it failed in about 18 months and we installed another type 35w.  Its a smaller pool, about 10K gallons and the 35w is like a spot light, the previous were more like floow lights and looked much better.  Two questions…

One…we have an issue with the light unit staying in place.  Seems it does not take much to dislodge the cover on the clip part and as a result the casing slides to the side only beling held by the screw on top.  Believe it is the Polaris cleaner that causes this. It has come lose before and the last time reinstalled by a fellow who does really good work so Ibelieve it was installed properly but obviously not holding…is there something we can install that will help keep this in place

Two, to get more of a spread on the light, is a lower wattage the answer?