I wrote a big long post and edited to just focus on the issue and ask for solutions. 1/3 of indoor arena (middle) is frozen completely solid. Is there a way to fix this without creating a worse issue (chunks of ice)? IDK if mag chloride will work on ice like this? There is no way to work anything in, it would need to be topical. Forecast is highs in single digits, lows below zero.
Washing legs after riding is not feasible in these temps.
Any cost guestimates or best places to buy whatever you suggest is also appreciated.