When I make Catfish oil my return is about 12 ounces to the gallon when using whole fish.
I vent my barrels under ground,with a plastic hose with steel wool in the end.
I auger a hole 18" deep insert the hose and add gravel than cap with dirt,very little odor with this setup and I've never had a fly/bug problem.
As far as carp for oil I've found them to be a poor producer of oil, but the end product does have some value in lure/bait formulations.....B.....

brian thanks for the tip i think i will go that route with my venting

The guys who put in wells and pumps work with check valves to help the pump keep its prime you may find one talking to someone who does wells . I think they are designed for fluid. Us guys who do refrigeration and A/C also use check valves depending on what part of the refrigeration system they are installed they flow gas as well as liquid .You may find one if you know anyone who does A/C Refrigeration guys use them more. Your oil making may depend on what species and how long you are willing to let it sit . I live at the coast , when I catch bluefish a taylor blue and a little bigger mostly they have a big depsit of fat / oil right on their belly and on their back as I clean my fish to eat I cut this fat off and just throw that part into 5 gal buckets. The difference is you get much less juice a lot more oil HTH pal good luck

Looks alot better than my 5 gal bucket sittin in the sun! I didn't vent mine at all, hope this doesn't cause a problem?

pappy i hope you have it a loooooong ways from the house just in case

LOL, it's only 50 yards from the house Bigtime and yep!, when the wind is right the smell is rather FRAGRANT!!!

you're going to need a long straw to suck the oil off.

Wasting good food like that is criminal.

If you're using whole fish, the DNR might be interested in what you're doing. Its been a long time since I lived in Wisconsin but it seems there might be POSESSION limits these days. Unfortunately, some wardens don't care that you're not using the fish for eating. So, be careful what you do and who you tell.

I want to see how the carp oil turns out! Me and my bro can shoot 750 pounds of them in a night.

big bob if you read all the posts you would see that im only using the catfish i catch in a big cooling lake for a coal power plant and the fish are basiclly unediable. the cats i catch in the rivers i still clean and eat im only going to use the head and belly meat from them to make oil.

as far as posession limits i will check with my local warden but i think i can get a commercial fishing license to avoid problems. thanks for the heads up

I have used the tea jars with the spigot at the bottom once I know it is done separating just open the spigot let the juice out until only the oil is left HTH

what about a filter for a fish tank plumbed in to your lid, would that keep the flies and bug out?

doogie it sure will on bait buckets best thing that ive tried

i was thinkin the same thing

Sure be interesting to see how it works out for you. Contrary to Jonathan's kind comments, I've only dabbled in this venture on a small scale and my findings were it's WAY better to just couch up the money for it. Maybe I should of jumped in with both feet like you, lol. Time will tell...

~ADC~

The fish oil if not pulled off will pick up the rancid fish smell.

thanks for the tip bravehart