First of all, if you haven't yet, have his teeth looked at. I'm going through this same issue with my 30 year old mare. She had been eating soaked alfalfa cubes until recently. I think that the alfalfa stems in the cubes is too coarse for her so I tried Purina Hydration hay. She still can't eat it so we are now serving up a large bucket of gruel three times a day. Her recipe is:
I soak for a minimum of four hours (only because that's how long the beet pulp needs to soak). You have to use a LARGE bucket. I add enough water to cover the pellets twice. Then soak until time to feed. Just before serving I add enough warm or hot water to make it the consistency of slightly watery oatmeal. After feeding one bucket I start the next meal soaking. I am considering reducing the volume a little per feeding and adding a late night feeding so she'll get four meals a day.
ETA: I don't think the hay stretcher pellets are meant to be the sole source of forage.
"My biggest fear is that when I die my husband is going to try to sell all my horses and tack for what I told him they cost."
I think it is scary to feed pelleted feed that is not soaked. Every choke we have had involved pelleted feed.
We fed a 37 old guy shredded beet pulp and alfalfa pellets with a scoop of senior feed, soaked. He lived on that ration for 7 years quite well. He was fed twice a day and looked great the day we had to put him down due to unrelated problems. Good luck!
I feed a mixture of soaked alfalfa pellets, beet pulp and a small amount of senior (flavoring) to my 24 year old stallion who has very poor molars. He cannot eat hay or grass any more. He looks fantastic and is maintaining very well this way.
Our 28 year old pony is thriving & looking/feeling better than he has in years on a mixture of Speedi-beet (flakes that look like corn flakes & ready to eat after 10 minute soak), TC Low Starch, TC Lite, and Standlee Timothy/grass pellets. I make it fairly soupy and he loves it. I feed 3 meals usually but sometimes add a meal of Timothy pellets mixed with water as his nighty-night