corys and guppy fries

ive been raising my 15 guppy fries for about month now and luckly none hav died so far , i am getting a tank for them when they reach about 3 months. but rit now i hav them in big bowls. i was wondering if i could put a small cory in there to clean up some messes at the bottom, i do a water changes on them about every other day but now the fries are lazy and wont move tat much anymore , im not sure if its in their nature or its that they get moved to much bcuz of the water changes, should i put a cory in or keep it how it is? :y_the_best:

 

I would suggest continue doing what you're doing now but go ahead and get the new tank now so that you can have it cycled by the time you plan to move them.