Blue Tit Nest Problems

Hi everyone,

I bought two nest boxes and had them on a veranda balcony, no activity, and when I thought I could make the derelict long iron flowerbox (100cm x 40cm) a nest, I lifted it up to see to my delight a clutch of eggs in a nest, so the parents have used the drainage holes which are now at the top to come in and out and the indirect light falls over the nest (so clever) I have put a little webcam at the back end, and they have been busy furnishing the entire box, quite a long box.

I have been watching them grow and get fed, there are about 6-7, however the hatchlings are still bald, with a tad of fur and their eyes still closed, however I watched on the nest cam, that a baby had just clambered over the centre of the nest, and struggled to find its way back to the centre, the mum didnt seem bothered about helping it back in at all. and for a few hours it was getting no attention and no food, the chick just got lost more and more in the big nest.

While I watched the parents fly away, i put on some surgical gloves and very very gently but very quickly picked up the stray and put them back in the nest, however to my sorrow, i also found a dead chick at the end of the box, that had suffered the same fate and wondered off and perished in the darkness of this big nest.

Any suggestions on what I can do to stop an more chicks perishing, I realise we are not supposed to interfere but most other nests are so compact and cosy this wouldnt happen and they couldnt crawl off until they were ready to fly from the nest.