Another Stocking Question!

[TubbyLaLa]

Juwel rekord 60L internal filter planted + well oxygenated
78 degrees F
Nitrates 20
Nitrites 0
Ammonia 0
ph 7.6
Tank is just settling for the moment after a tank re-shuffle, current stocking is
5 x male guppies
5 x Xray Tetra
2 x Amano Shrimp
2 x African dwarf frog
2 x peppered Corydoras
(I know these guys might be happier with some more corries in there but they are healthy and chirpy fellas at the mo feeding well and quite active)
Thinkfish is down soo can't get stocking levels from there just wondered how much more room was in the tank?
Not much I think? I have a spare filter if I need to add another (fluval 2 plus)
Thankyou

 

[ox5477]

I would add 4 more cories atleast and maybe 3 or 4 more tetras, but beyond that, no more....