DavidBliss, we use Cutrine Plus for algae control. Often the dead algae will mat on the surface, and raking or breaking up the mats is all that works for us with that. At least here at our place in NE TX, we get early winter olive colored FA that stays active until the water temp starts approaching 60-65 degrees. I'm not sure how water temp affects all this, so maybe Bill Cody or others will chime in on that.
A cheap laser thermometer, and box store glass tube pool thermometers are what I use for water temp. With the glass tube thermometer, I tie it to a string, and throw it out 10-15'. The reason I use both, is so both the surface temp, and subsurface temp, can be monitored. I usually hand feed in the winter, and the subsurface temp lets me know what temp the CNBG are actually residing in. I rarely use thermometers after May when the water permanently warms up, but I use them a lot in winter and spring.
Hope this helps.
