Welcome to the forum.
Do you know which species of pleco you have? Some reach 2 feet long.
You'd be best served moving those bala sharks now. If you wait until you feel they're too big for your tank, they're probably already suffering from stunted growth. The balas require roughly 50 gallons for juveniles, 100 for adults.
Frogs do best in species-only tanks as when kept with fish, they quite often don't get their fair share of the food. There are many options for snails or shrimp, what do you like?
75: blood parrots, featherfin cat, emperor tetras, turquoise rainbowfish, BN plecos, japanese trapdoor; 46: WCMM, gold inca snails, ghost, bamboo & amano shrimp, kuhli loaches, rummynose & ember tetras, endlers, platies, flame gourami, guppies; 16: pygmy, peppered, loxozonus corys, otos, assassins, RCS ... ~ Research PRIOR to purchase.... ~