DIY Fish Leather

I am trying to make fish leather. I really want to use some - fill it with water, perhaps make some fish skin water balloons. I have sourced some form Walter Reginald in London, but I am struggling to ascertain what  chemicals are used in the tanning process, and I don't want to run water through heavy metals. So I thought I would try and make some of my own. 

Had some mackerel in the fridge...apparently you can make it with any fish, although the stuff you get from Atlantic leather seems to have more of a snake skin look than I have achieved. Its really hard to get the flesh off without ripping the skin, and it is definitely tougher in some parts than others - but I also noticed that when I looked at some of the manufactured stuff at the sustainable materials library. 

So, you have to de-scale, de-flesh, and 'tann' in a mixture of oil and egg yolk (1 dl oil : 1 egg yolk) or use 50% urine and 50%water  ( preferably from a boy) see: Tanning Fish,  I left mine overnight to tan, have given it a good cold wash and it is drying now...

These patches where the skin colour comes off are not holes - they have a pretty tough translucent and patterned skin on them. I didn't realise the coloured part of the fish was behind this - and not on the outside. 

Its interesting that it so hard to find out what chemicals industry uses, and that often there is a surprisingly simple way to do things DIY. I 've yet to see if it works for me.  I think I might need a bit of practise,  I might have a go at some salmon at the weekend. 

The flies are after the leather.