I have no idea since i have never delt with minnows, but since no one has replied, i'll give my unprofessional opinion. I have fed turtle food, fish food, cat food and all kinds of food to fish, im sure the minnows will eat it if they aren't stressed out. As far as the food keeping them alive...I don't know, but it could depend on the size of the storage tank and the quantity of minnows. I know colder waters will hold more oxygen, but with more minnows consuming the oxygen they may die from lack of oxygen. Let me know if i'm way out on left field on this one. It could be just unhearty minnows. If you want to keep them alive longer, you could get a little 10 gallon to keep them in with air bubbles and food. Room temp water should be fine, and it appears colder waters wouldn't hurt as well. Good luck and hope this helped.
Jeff M.
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Jeff M.
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1.2 tri-colored hogs
2.4 w.hogs
1.2 albino RES
2.4 spotted turtles
0.1 puppy
--->2.7 albino mice feeder breeding colony 