Pond Boss Forums Thread Like Summary - Controlling weeds in my new 5 acre lake

We dug a 5 acre lake here in northern Indiana 2 years ago and I have been adding pond dye as it has been filling. We haven't stocked it with fish yet but when it's full I am planning on adding some to help with the bugs and weeds (open to recommendations!) It still has about 3 feet to go before it's full. As the water has risen, many of the weeds on the banks are now submerged and appear to still be living. I can also see some submerged algae in some places along the shore. And it appears cattails are starting to shoot up in various places. Looking for advice on what you all would suggest for herbicides to control the green stuff. I was originally going to use copper sulfate to control the algae but it seems there are a lot of folks who are telling me that is a poor choice since it can't break down and will leave the bottom sterile and could actually create additional phosphorus in the process. So I was thinking that I could use Cutrine Plus (granules) or Duiron for the algae but maybe you guys recommend something different? And for the underwater weeds would Diquat herbacide be the best choice? Would that also kill the cattails or do I need to use RoundUp for that? I'll take any advice you guys can give me!

After extensive product testing for EPA re-registration , it was found that Durion killed all or most of the entire base of the aquatic food chain and I think EPA considered it too harmful for a healthy pond ecosystem. Ruin the food chain = ruin the fishery AND the other many natural balances within a pond - lake. Here is an older discussion from the Pond Boss Forum about durion (aka Karmex). Note the results in the link below for animal testing using durion.

https://forums.pondboss.com/ubbthreads.php?ubb=showflat&Number=288581#Post288581

Here is something from the link where they studied the affects of Durion (Karmex) in laboratory studies.
A part of the article says - "" This chemical may also cause changes in blood chemistry, increased mortality, growth retardation, abnormal blood pigment and anemia, as seen in animal tests in the laboratory.
Some other symptoms show decreased body weight of offspring, wavy ribs, extra ribs, delayed bone formation, reproductive and embryotoxic effects. Other side effects include methemoglobinemia.""

Thus IMO if there are pets drinking the pond water with Karmex it could affect their health. This also causes me concern if there are children swimming in the water where their absorbent mucous permeable membranes are exposed to the water with the durion / Karmex dissolved in it. Usually the younger the animal or plant the more influence the chemical has on it. All the above is probably why it is not labeled for fish and recreational pond use!

Diquat just gives the cattails a haircut, it doesn't kill the roots. You want a systemic herbicide. While the other two chemicals are more expensive, I've found that they work better with less re-spray needed. Of course being a different chemical and working differently on the plant, I have to be careful of translocation. I always add a surfactant @ 1 fl oz per tank mix gallon and also add an aquatic dye to show where I've sprayed. With the Roundup Custom, mix 0.75% solution and apply 2.3-3.75 quarts per acre of active ingredient. Since there is no surfactant in Roundup Custom you have to add your own.