Should I add more filtration?

[Cookie_discus]

I currently having a ac 110 with floss and seachem matrix running on my 53 gallon tank. I am wondering should I add a ac70 for more filtration? The livestock I have is 4 discus (all of them are 3.5''), 11 sterbai cory catfish, 6 cardinal tetra and one pair of apistogramma agassizii. I do 30% water change once in a two days.

[JBurgo]

What are the results of your water test just before WC?

[bluelagoon]

A 110 AC should do that tank with ease.They are rated for over a 100 gal. tank.Perhaps you should up WC's a bit;not that there is not enough filtration but water depletes no matter how well filters work.