I recently started my 2 horses on Hoffmans Minerals at the end of January. To ensure they were getting enough, I added 200 gr to their daily feedings. The one mare (Jade) stopped licking her bowl out, so I cut her back to about 100 gr, the other loved it so I upped her to 250. Just this week I stopped adding to their feed and put it out as free choice. It's disappearing! Someone is eating a lot. I guestimate I put out enough for 3 days and it was gone in one. I put out enough for two days today and we'll see what they do, but as I was leaving the barn, Jade was at the minerals already. I've gone through almost 1/2 a bag in probably 6 weeks.
The Hoffmans web site says free choice is fine and if they are eating more than 200 gr a day to put out salt. I do have salt out already and one of those red mineral blocks.
Selenium is only given to them in the Hoffmans (15mg/kg), unless there is some in the red mineral block. Their only other feed is free-choice hay and about 1-1/2 cups of 12% pellets daily.
I have always been a proponent of "they will eat what they need and leave the rest" but how long would it take for them to get their mineral needs up to snuff if they've been lacking for years? In other words, how long should I continue to leave the free choice out without worrying about negative side-effects, if any?