Filtration??

[KaiserSousay]

but being at school the majority of the year my parents dont take the care I would be with water changes and etc.

So, now that the folks finally get you out of the house for at least part of the year, you want to keep them busy looking after your new tank.
What kind of stock is in the 40?
Tell me you are not going to add more fish before you go off to school.
Those 2 filters kept the 40, with no stock additions they will keep the 90, as well.
With no added stock the 90 will need less care.
Just can`t beat a better than twofold volume of water increase.

 

[philfreenode]

filtration is not a substitute for water changes. if your parents or anyone else at your household is not going to maintain the tank honestly you shold rehome the fish in the tank. a tank shouldn't go more than a week (or two) at most without water changes. there are people on this site who might change their water less, but i'm sorry, I can't agree with that practice, fresh water fish love fresh water. would you like to go more than a couple weeks without taking out your trash?