Should i add this small filter

[Country joe]

I have a 200 litre community tank with mainly Tetras it has a Fluval 307 external filter, but I have a small Fluval mini 45 litre filter sitting in a cupboard doing nothing.
Would it be worth using in this tank, and if yes would you set it up opposite the current out flow?

 

[Uberhoust]

Under most circumstances, a 307 should be able to keep up with your tanks needs, though there would be exceptions. More filtration will not hurt anything except perhaps making too much current. This is really a "it depends" type question. Without knowing how stocked and with what it would be difficult to determine if the extra filter is worth the extra effort.

 

[MaloK]

If you are able to put it somewhere that it's not too disturbing. It still makes you a seasoned filter that you can use to crash install a completely cycled setup in a snap.