Help Me Pick A Grain

I am needing to decide on a grain for my two mares. One is 13 yrs old and is in moderate work (1-1.5hrs 6 days a week with jumping and longer trail rides) who needs to put some topline on (had EPM in the fall and is still “rebuilding” what was lost) and maybe another 100 lbs. The other just turned 5 and is in no work, but needs to go up a score or a score and a half on the BCS scale. We also believe she is growing again. They are both OTTBs.
Their current living and feed situation:
*Grass hay 24/7 (will be going to brome soon)
*Beet pulp 3-5 times a day (lunch and night check and some in between). Unsure of amount as the BO feeds it throughout the day
*Stalled roughly 16-20 hours a day and turned out for a few hours in a small paddock together (no other horses) with several piles of hay. Currently too hot for day time turnout, but hopefully we will have access to an additional turnout pen for night turnout soon.
*12lbs of Kalm Ultra split into 2 feedings
*2lbs of Renew Gold split into 2 feedings
*1-2 cups oil split between two feedings (the younger mare recently decided to stop eating oil)
*Custom Vit/Min supplement with extra Mag and Vit E and a “double dose” of Triamino

I think the Kalm Ultra is okay, however I am having to go 20+ min the opposite direction of my barn to get it and they keep running out (like we are now). The feed store near the barn will be getting it in July but I need something in the mean time. I have access to just about every brand but the feed store near the barn carries: TC Senior, Tribute Safe N EZ, Buckeye EQ 8, and some purina and nutrena feeds. They were previously on roughly 10lbs a day of the Buckeye Safe and Easy Performance and were not picking weight up weight whatsoever which makes me want to stay away from Buckeye. My barn owner is really pushing the Buckeye Eq 8 which is like $25/ bag because she says it helps the gut a lot, however all I have seen that is different from a “regular” feed is added probiotics (which I picked up a tub of Probios and started them on that but neither of my horses seem ulcery and both have been treated for ulcers within the last 6 months). The older mare has previously done well on both the Tribute Safe N EZ and Purina Senior Active. I would prefer to use something like the Safe N EZ as it has no corn or molasses and a lower NSC, but worry that won’t be enough calories to put the pounds back on. Both horses were maintaining well on a grain free diet (free choice grass/ alfalfa, Renew gold, Oil, and a vit/min supplement), however we moved to a different barn and had severe issues with feeding (they weren’t being fed at all) and then another that did not feed enough hay and they are still “recovering” from that. Ideally, I would like to transition back to the grain free diet when they are both at a good weight, although that may not work for the younger mare.

Can you show us photos? A healthy horse is 4.5 to 5 on the Henneke scale, no higher. Is your 5 year old really a 3 out of 10?

I say this only because we often see photos of horses that are over weight but have deteriorated back muscle.

Also if the standard at your barn is obese, a 4.5 horse can look sickly in comparison but actually be racing fit.

If weight truly is the problem, feed more hay.

If the problem is lack of muscle, you will want to boost protein and also make sure all the vitamins and minerals are covered.

You might be well served by a ration balancer with the limiting amino acids and also by adding alfalfa hay.

If the horse truly is skinny and needs more concentrated calories you could feed more beet pulp or a higher volume feed.

But the other components of topline is exercise. Horse should get as much turnout as possible in a large area and correct slow work in hand and under saddle.

Scribbler - Don’t forget to read all of the OP please. They are already getting hay 24/7 and by that I mean there is roughly a half a bale in their stalls 24/7 and even more in turnout. These horses do not want for hay, trust me. But they did lose weight in a previous situation where they were not getting enough hay. I can take pictures tonight but I am have been having the worst time getting pictures to post here so may put them in a FB album. Again with the protein aspect they are getting a double dose of Tri Amino daily in addition to the grain which is 12% protein.
What would be an example of a higher volume feed?
Again, more turnout is not possible and the younger mare is not sound to be ridden or worked. The older mare is gaining back from what she lost when she had EPM and was out of work for close to 3-4 months. She has been back in work for roughly 3 months.
ETA They get BP several times a day. I honestly do not know how much/ how often, but the BO is feeding them small servings essentially all day - as soon as they run out in their pans they get more.

First, you need to know what weight of beet pulp your horses are getting.

Second, it would be useful to test the hay to see how nutritious it is.

Third, it takes time to put on weight. If they are visibly gaining week over week, that’s all you can hope for. Maybe you should start taking confo shots or use a weight tape once week to chart progress.

By high volume feeds I meant the feeds where the minimum recommended feeding is 4 or 5 lbs a day as opposed to a ration balancer that is 1 lb a day.

You are already feeding a very high amount of hard feed. Is it not helping?

Thats unfortuantly not possible - neither weighing the BP as the BO soaks two large buckets and splits it between all the horses nor testing the hay as we are about to get a new batch of a different type of hay as stated in OP.

I am already feeding a high volume feed? I am not sure where the idea of the RB came into play.

It is helping. The issue is not finding a grain period it is selecting a grain from the options i have that will be available consistently.

I can update with pictures, however it seems the point of the thread was missed.

https://youtu.be/LnzaFgXmBHA

The first 4 pictures were taken today (grey is the older in work mare). The first two comparison photos show the before (early May for the bay and mid May for the grey) on top and after on bottom. The last photo shows what she looked like a year ago, and what I consider her ideal condition, on top and today on bottom.