Most algae eaters are bottom level fish so they would be severely stressed out with the crawfish... if they have enough sense to stay in the upper layers, it would still not be their normal lifestyle and they would have problems related to stress. I'm sure your other fish are getting stressed as well. Imagine having to live in a room where you know someone in that room wants to kill and eat you.... wouldn't you be stressed and afraid to go to sleep?
'm interested in your reason to say the CAE will be stressed!!!!!! or any fish come to that. i take it you have tried to keep these creatures together? its not a fair question, as most US Cray are aggressive and none tropical, so cant be kept withthe fish mentioned!!!!. but there is a member here who has kept a p. clarki in a community for 2 years with no loss of fish.
just incase you haven't
so some advice from someone who does!!!
given a careful selection of you crayfish, covered in a thread, within this section. my CAE lives a happy and stress free life. as do the 3 plecos, 2 corys, 1 uds cat, 1 feather fin synos. ohh and a pictus cat, lol who sleeps right outside the Crayfish den. it seems if your cray is going to take fish, they are more likely to take angels and gurami, as opposed to ground dwellers. but will jump at the chance of sick or dead fish
Crayfish are opportunist feeders, not hunters! though most Cray types like, protein, when younger. as they age the seem to lean towards veg. any hunting is a learned or forced action, bad feeding causes a lot of lost fish. and incorrect introduction, may well cause the rest.
good feeding, high oxygen and a mature tank will all add to possibility of a calm tank. but things still go wrong, so if the basics are not followed, perhaps it the keeper who's causing the problems not the Crayfish!
will2, 60 liters is too small for a loan redclaw, imo, never mind fish too. i would say you need at least twice that, to keep fish as well. Redclaw, the only legal cray in the UK, is probably the most chilled of cray, giving us the change of having a true Crayfish/fish community. take a look at my thread, it may be of help.