The Reward/Cutrine mix does well on pondweed...it should give you pretty good results. As far as what the fishfarm guy was telling you...cutrine killing grass carp and Reward killing filamentous algae...I don't think so. I spray ponds and do fish work for a living, and in a lot of the residential ponds, we have to keep them completely free of filamentous algae. Believe me, I have probably put more than 14 gallons of Cutrine in some of them in one summer
...and they still have plenty of grass carp in em. Maybe in his case with trying to control algae in recirculating tanks or something, Cutrine could cause issues. But, if most of your carp are gone, my guess would be they went out an overflow or something like that. I also pretty much have the Reward label memorized, and it says in there something to the affect of: it should only be used for partial control of filamentous algae...for full control mix with an approved algaecide
I agree with you that the tilapia and carp compliment each other...carp do well with submersed stuff and tilapia do well with algae control.
