I use potato, to prepare it cut it into 0.5-1cm thick slices then freeze them.

Then before feeding I defrost it under warm water, once it has defrosted you will notice that it is quite rubbery. When fully defrosted put it in the tank, it will sink and the veggies quite often make a beeline for it.

Some times they don't though so leave it for a bit until they get the idea, once they get to grips with it they will seek it out as soon as you put it in the tank.

The advantages of this method is that it doesn't break down like cu***ber and will remain viable for a few days.

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Alan

Thweeerp!