There are a lot of people battling the same problems, especially with TBs. We have an excellent product for Mud Fever and Rain Scald, which I'm assuming is what was affecting their skin.
If you haven't tried that yet, I recommend you start using it ahead of time as a preventative, just once a week in their water trough (1 capful), or if you prefer to buy the small pump bottle then you would do 2 doses on the same day, once a week as a preventative. For some horses this doesn't always work and the mud fever can still flare up but if you have the product there you can immediately go to the acute dosing regime and nail it before it gets entrenched. See Mud and Rain link at the bottom for acute dosing regime.
Re the hooves, we have a product called Abscess Protect which is not listed on our site but can be ordered by purchasing a repeat prescription, I'll put the link below. You simply state at checkout in the Additional Info section which product you are wanting.
Abscess Protect targets the assimilation of minerals from the diet, strengthening the hoof material. Some horses, no matter how many supplements they are given, will not be able to absorb them properly and end up with poor quality hooves. This product also builds up the immune system to try and prevent abscesses forming and keep on top of infections.
You can use Mud and Rain and Abscess Protect simultaneously. If they were to get an abscess, we have our Abscess Plus product. Its so difficult when the hooves are in water, so beyond creating horse gumboots its a challenge.
HERE'S THE LINK FOR MUD AND RAIN hippohealth.co.nz/search?search=mud for Scratches, Mud Fever, Greasy Heel, Mud Rash, Rain Scald and Rain Rot.
HERES THE LINK FOR REPEAT PRESCRIPTION (just use the drop down menu under the price to choose repeat and get the cheaper price) hippohealth.co.nz/search/prescription-for-horse
HERE'S THE LINK FOR ABSCESS PLUS. hippohealth.co.nz/search/abscess-plus