Keeping fry out of canister filter?

I have a ~1000 gallon pond in my yard. It contains mosquitofish and goldfish. The pond currently has 2 of these submersible filters similar to this:

However, to clean the filter, I need to wade into the pond, take the entire unit out of the water, and then clean it out. I would prefer a filter that can be cleaned/serviced without having to wade into the pond. So, I am looking at canister style filters like this:

which look like this when installed:

Now, here is my question: The mosquitofish have a lot of fry. Some of the fry grow up, and some of them get eaten by the adult fish. But, I don’t want to harm the fry by having them get caught in the filter. Is it common for fry to get sucked into canister filters and to get stuck in there?
If so, does it work well to put some sort of netting over the filter’s intake hose to keep the fry out? And, if you do that, then do you end up needing to unclog the netting often?