Sounds like you have it all under control. Please keep us updated on how they are getting along and hopefully the BComplex will continue to get those legs stronger an stronger.
Jumbos do get huge and there are ways to help them first make an easy way to get in an out of the pool then be sure not to over feed treats and be careful what treats you do give them. Carrying around all that weight will cause them to have leg issues and since they have already shown symptoms...
So you don't have a way for this one particular duck to get in an out of the pool with out a struggle? and your keeping the hobbles on when it's in the pool? Take the hobbles off when in the pool. and make a ramp of some kind for them to easily get in an out. Step stone on the inside so it...
Until they are laying age they don't need any calcium supplements they get that in their feed. once getting close to laying 5 months usually, then we put out oyster shell in a separate bowl for the layers and they eat as needed.
Also want to add they are getting too big for the chick waterer and feeder. To keep water from being splashed out and giving them a way to wash their faces maybe something like this? you can place the water container on a cookie try or something similar.
Aww I bet they love the ducks and the duckling love them. She may always have a bit of a problem more so than the other one but hopefully with all your doing she’ll do fine. If you get to take her please let us know what the vet says.
I’d say it’s def her hips but only a vet can tell you what maybe wrong. Xrays most likely. I’d just keep on with what your doing good feed the liquid b complex and the water exercise and out door time. Try not to have her running. Saying if you have children they might think it’s fun to get...
If she’s walking better in other areas then most likely it’s the concrete. And yes it will take some time. You are seeing improvement right. This maybe she was just born with hips set farther apart but I still think you can get her going really good. You could even lay an old towel or rug down...
Stick with what your giving for now . @casportpony is working on getting the dose down for everyone according to the weight of the duckling! That’s great your seeing improvement!!