if they are getting a complete diet which consists of Hay/pellets/veg/fruit,grass and dandelion type plants they are getting everything that they need,all supplements and vitamin/mineral type things are not needed,any supplements put in water is a complete waste of time as they never get the correct amount anyway and it can actually put them off drinking,you will probably only see them very occasionally using the salt lick and mineral block,i would take them out,they are basically money makers for big companys trying to rip small animal owners offxxxxxxxx