Force feeding is extremely stressful and should only be done if all other methods have been exhausted.
The first thing to do here is to separate the dragons. Its best to house dragons, especially young dragons on their own anyway. This allows them to thrive better, eat mor eand overall be more healthy. Young male and female dragons should never be housed together due to risk of breeding at a young age - its possiblke the wounds your dragons have suffered were a result of breeding attempts. There is also a possibiliy that one of your females may be gravid already - i hope this is not the case as this can be an extremely dangerous condition for such a young dragon. Since an attack has already occured there is no question that separation is needed. Ideally, put all three beardies in separate containers, since one of the females is having trouble eating she would have a higher chance of improvement in a separate tank - however, at the very least you should remove the male and house him separataely.
As the above poster mentioned - it you have a MVB that is new (less than 6 months old) ther is no need to have additional UVB. It may or may not be harmful - i would remove it as its not necessary.
What are the temps in the basking spot in your tank? How are these temps measured?
After separating the dragons - make sure everyone has good basking spot of 110-115degrees, good uvb etc.
Since the female hasnt been eating very well, soaking for 10-15minutes a day will help maintain her hydation. Soaking should be done in warm shoulder level water.
Give them a few days to a week in their own tanks with good temps etc. If you dont see an increase in the appetite then i would contact a vet. Its possible there is an underlying infection remaing from the bite wound which is affecting the appetite. A course of antibiotics may be needed.
If there is no infection it may just be a matter of giving them time int heir own tanks to relax. Continue to offer food, soak or mist daily and see how they do. If she will not eat you can make up a slurry using baby food (chicken flavored, squash flavored) some calcium powder, some feeder insects, ensure, and pedialyte mixed in a blender. Dont force this food - but start by dribbling it onto the dragons lips and seeing if she will lick it up herself.
Keep us posted!
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