Hi. I hope island life agrees with you and the withdrawal systems of not having to brave rush hour traffic around Manchester aren't too severe. I take it that RA50 is basically the same as Ilford Wetting Agent. I have used this after rinsing since first going on an evening class B&W course in 2003. I must have put dozens of 35mm films through it. No problems with any. Of course the film is only in it for about 2 mins.How long was yours in it?
At the evening class it was a pity in some ways that students didn't leave their films in the wetting agent for a long time then I could have said that even then, no-one had any problems. I don't think anyone went away for say 30 mins, leaving their film in the wetting agent tank but I don't know. However the tutor had dealt with a lot of classes and knowing what students are like, I feel he would have warned us about not leaving film in the agent if this was likely to happen. I can't say that the agent was Ilford but the dev and fix were so it's likely that it was.
So that experience at nightschool combined with what wetting agent is and does suggests that the problem may lie elsewhere as Dave suggests. Things such as temp and maybe dilution or batch of rinse aid? Key to cause is whether Fotospeed RA50 is new to you. Like Dave, I take it that it has never happened before but of course you may have dispensed with rinse aid until now.
Sounds as if it has completely ruined your film. If rinse aid has this potential it sounds serious enough for manufacturers to issue grim warnings on containers and I have never seen any. It's a real mystery to me. My condolences.
pentaxuser