I feed Aquamax 600 & 500, about a 9:1 ratio. Usually 8-10 cups a day (it's a half acre pond), up to 6 days a week (2-3 days a week so far this Spring).
TJ:
It could be an F1, but based on the typical appearance of my "have to be" F1's over the last 10 years, I think it is more likely some indeterminate Fx (or possibly an F1 backcross with a RES).
"Live like you'll die tomorrow, but manage your grass like you'll live forever." -S. M. Stirling