The Mazuri 5M30 is a good breeder mice diet, with at least 16% protein and 6% fat. Adding a basic seed mix for variety won't hurt either, or whole wheat/grain cereal (ie Cherrios) makes a great treat too (non sweetened cereals (ie no fruit loops and the like)) and a way to hand tame mice too.
The 10 gallon tank is way too small for 8 adult mice, much less them and babies. This is likely the main reason your males are eating babies (and probably the females too). Also, glass tanks are crappy rodent cages...it tends to have poor ventilation (down on the 'ground level') and ammonia from urine etc. can get trapped in the tank (not to mention it can overheat too...)
What I used to use for a group of 1:3 mice was a fair sized rubbermaid tub. It was deep enough the mice couldn't jump out of the tub (though never hurts to put on a lid (just cut out most of the center of the lid the tub comes with and replace with 1/4" wire mesh (hardware cloth))
Find a tub that has rounded corners and very shadow or no 'feet' indentations inside. This greatly reduces to completely eliminates the mice's ability to chew through the plastic. With a tub this size (I think it was something like a 110quart tub...though could get away with 75quarts). I had all kinds of toilet paper and paper towel tubes in there, 2" diameter PVC pipe sections, and other cheap paper/wood 'toys' for the mice to chew and play in, to keep them occupied (if bored or stressed, chewing though cage sizes tends to be the favorite pastime, if nothing else is there for them to play with). A wheel or two is also great addition. Make sure the wheel is free standing and has at least a mesh cover (solid is better, but never seen any of these that are free standing, most are designed to be mounted on 'bar' style cages..(and I don't trust the bar style cages as i have had adult mice squeeze through the bars and escape in these before, not to mention mice climbing all over the bars, tend to urinate out through the bars...and you end up with gummy smelly bars and 'splashes' of urine all around the cage).
Having two wheels ensure the mice don't end up fighting over who has the wheel (three adult mice on one wheel is amusing..but four or more..usually results in one or two mice clinging on while they are spun around like on a Farris wheel.
I also had side mounted wheels jam up (either mice bury it in bedding...or other objects get underneath it) and mice get trapped between the wall of the cage and the edge of the wheel, resulting in having their sides caved in.
The stand alone type also are less noisy and are pretty sturdy. The 8" diameter ones are the best size for mice...if I recall correctly.
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PHLdyPayne
