If you have sand as a substrate then no worries about stuff down in it. All it requires as I'm sure you already know is to hover the siphon over it to get debris out of it. the only other thing I can think of is over feeding because snails will definatly breed according to how much food is available.
Doing an extra 25%
water change each week for awhile and cutting the food down should help. The Clown loach needs to get hungry enough to eat the snails so maybe feeding the tank one small feeding a day and even skipping a day each week may help( I skip the day I do water changes). I understand wanting to get rid of the snails

and the clown is your best bet.
I see you have two plecos. I don't know anything about the clown pleco but the Gibby eats and poos. I have one that started our as a 2inch fish and is now about 5 inches and still growing. Plecs are heavy waste producers. Their digestive tract is so straight and short that some of the food they eat doesn't get digested so there is another food source for the snails.
I wouldn't tear the tank apart yet or get rid of anything (copper based meds will kill some plants also) or dose with chemicals.
Trying these things suggested will take a little time to show results but in my opinion it's the safest way to do the job.
Carol