Thank you friends for an interesting discussion!
Reading the forum, I assumed a similar view.
I will allow say my opinion.
1. Feeding of live frogs.
a) Parasites are known, they are very specific and are harmful particular species of frogs.
b) Infestation victims virtually impossible. Frogs can be intermediate hosts of the parasites to other animals (eg: mammals), but this does not apply to others frogs.
c) Any predator has a strong immunity to viral and other diseases of the victims. Pacman - a real predator.
d) All feed frog caught in ecologically clean place.
2. Winter feeding seafood.
a.) Use molluscs that contain protein and micronutrient elements easy.
b) I do not understand why in marine molluscs should be a lot of salt (what kind of salt?).
For example, I also do not understand how Pacman feed crickets and cockroaches, if you look at the structure of Pacman.
picture №1

Image source
Reptipedia, the Reptile and Amphibian Wiki
picture №2

Image source
Wikimedia Commons
picture №3
https://imagizer.imageshack.us/v2/70...0/703/9vnv.jpg
Image source
Skeleton of the week 26
The presence of strong skull, teeth and jaw strength indicates strong predator.
Cockroaches and crickets - is fodder for the weak frogs.
I said my opinion and it is good that you have other rules feeding Pacman, may be compared.
Thank you.