Spa tone iron replacement water

[Brid75b]

My 4 year old grandson is on spa tone having real trouble getting him to drink it tried apple juice orange juice black currant etc need ideas to disguise the taste

Is he having the flavoured one or the plain? The plain one is quite strong. The apple flavoured one is still quite sharp but probably easier to then disguise in squash or something?
I assume this is on a Dr's advice about iron levels - is there a children's prescription supplement he could be prescribed instead? Although that may not taste any better I guess.