Fruit cage 'roof' netting support.

I have a fruit cage about 12 foot by 12 foot and I would like to support the roof in some way.  I have some thick walled blue plastic tubing, (I expect you know the stuff).  Would it forget its memory of being coiled if I held it straight and poured boiling water through it and waited until the water cooled? 

I could also use plastic electrical conduit but that would mean shelling out the folding stuff and that might buckle under the weight of snow!  I'm thinking of something like an inverted catenary ?

Over to you knowledgeable and resourceful persons! 

Cheers and thanks in advance.  Tony.

I thought it was recommended to remove roof netting over the winter on fruit cages because of the weight of snow & to let the birds in to feed on the pests. Does that solve the problem

I thought it was recommended to remove roof netting over the winter on fruit cages because of the weight of snow & to let the birds in to feed on the pests. Does that solve the problem

I must say I do take all the netting off mine once the majority of the crops are picked, so the birds can finish the few that are left and eat up any bugs lurking, so never have to worry about snow