Unhappy sick girl on my hands

[Byrd gal]

My girl is sick again she is not out and about with the others. I noticed she had feathers coming in but today she is pooping watery yellow and that can't be good. She is eating and drinking a little. Crop is fine breath ok for a chicken I suppose. Her stomach feels firm, not supple. I gave her a soak, no bugs, 600 mg calcium and a dose of poultry vitamins. She is 4 and lays off and on. Would this be internal - age or a parasite problem?

 

[Byrd gal]

Forgot to add last time she had sour crop not poo issues

 

[Byrd gal]

Today she is leaking clear fluid with some yellow her underside is soaked. I started fish mox 500 mg tablets. I am at a loss here. I have never had a girl in this much distress. She squats and pants walks with a waddle. Heavy feet. We are in trouble!!!

 

[Byrd gal]

Picked her up and she leaked clear fluid from her backside and this after a soak yesterday please help me