Feeding festivums

I've had my festivums for about 6 weeks now, and found them virtually impossible to feed. They have shown no real interest in anything I have offered them, including flake, frozen food and even, in desperation, floating pond sticks.
The only time they've ever shown an interest in anything was when I put a few live gnats under the cover glass, which they enthusiastically picked off the surface.

Since I've been away from home for the past 5 weeks and the OH has been in charge of feeding, live flies has not been a viable option. I got home at the weekend to find 3 of the original 4 alive but still not feeding.

Tonight I chucked a few small guppies in the tank and the festivums went mental for them! I'm relieved that at last I've found something they will eat, but it's going to be pretty inconvenient having to maintain a tank of guppies just to keep the festivums going. I could try them on daphnia and insects from the pond when the warmer weather comes along, but that in itself could be problematical, not least because it's seasonal.

So the question is, what do peeps suggest as a way of weaning them off live food and encouraging them to take flake or frozen food? Or do you think I'm stuck with having to feed guppies forever more?

now you've given them a Roast Dinner with all the trimmings, they most likely wont fancy bread and butter now anyway  :2funny:

how about trying them on live crickets/locusts?

Yeah Nic, I'm planning to feed them more live insects, but I'd rather get them to take other types of food as well. But now they seem to prefer to starve themselves to death rather than touch anything that doesn't wriggle.

It's a worry cos I work away from home a lot and although the OH is a wizard with the pinch of flake it's too much to ask her to start playing around with beasties that she's scared of anyway!