Does anybody know where I can buy swamp cooler valley trays. The trays that distribute the water to the filters.

For two summers I have lived in my rental home that has an evaporative cooler. For two summers I have suffered miserably. I live in Phoenix so for most of the summer it isn't bad because of our "dry" heat but when it gets humid, it can get up to 93 degrees in my house. This is not good. Management has insisted that the cooler works just fine and that nothing further can be done to make it cool more than that. I don't think that's an acceptable answer and I want to try and find a solution before it gets in the 90s in the house. Someone told me yesterday that there is a "tent" that can be put over the cooler so that it will draw the air off of the roof surface. Supposedly this is supposed to help the cooling. Has anyone else heard of this? Minimal searches so far only provide cooler covers and do not say if it helps with cooling at all. Any advice that can be given is greatly appreciated. I don't want to melt! I would like to see the winter. Thank you.