A periphyton mooring was developed that allows simultaneous measurement of rates of periphyton accrual and many depths in a lake or reservoir. The array can be suspended from floats or submerged to avoid vandalism. Several arrays that were deployed on Campbell Lakes on Vancouver Island produced amazing accrual curves showing detailed growth kinetics. Detailed light, temperature, and nutrient concentrations were measured using sensors and depth-specific sampling. Models having very high fit to the data were produced showing what conditions really drive and limit periphyton growth in these lakes. These models can be linked with Digital elevation models to show detail on how periphyton changes with changing water surface elevation…super informative for reservoirs. All is being presented at the November 2017 meeting of the North American Lake Management Society in Denver, USA.