Why is this not more popular?

[FishTank84]

I've been thinking about converting my overflows into more trickle filters. Are there any cons of doing this? Seems like a great use of space to me.

 

[Fish Tank Travis]

The only issue I see is that it will be very hard to clean the detritus that gets stuck inside.

 

[Hendre]

The only issue I see is that it will be very hard to clean the detritus that gets stuck inside.

Absolutely agreed here. Unless you put your mechanical media up here by which point you can pretty much make an internal filter. However it would work any way as long as you can trap detritus...

 

[TwoHedWlf]

Yup, it's going to be a massive PITA to clean. Now, if you made up a basket that you could lift out to pull them all out at once or something similar then it would probably be usable.