It wouldn't hurt to have room to turn around. Since i'm from Canada and we don't have all the same equipment as you i don't know the filter you asked about but the capacity sounds fine. You always want as much filtration as you can afford. Matching filter capacity to your tank is fine, but it's always better to go one or two steps up.
I personally use Fluval, i don't know if you have that down there, but it's a really good filter.
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- Melanie
2.0.0 cats
0.0.3 crested geckos
1.2.2 leopard geckos
1.0.0 Bernese mountain dog
1.1.1 red ear sliders
0.0.1 emperor scorpion
0.0.1 chilean rose tarantula
1 south american cichlid tank
2 planted tanks with dwarf cichlids and platies