Sponge Filter, 20 Long

[demicent]

Would it be better to have one sponge filter in a 20 long, or two smaller ones at opposite ends? 

[Alec2cool]

I just use one of the "medium" sized ones on the corner of my 20 long

[Ken Dyer]

I would say two (one in each corner) is probably better, but (always that word) I don't run two sponge filters in any of my 20's.

Two sponges would theoretically create less dead spots, would allow you to rotate cleaning filters, leave you with a "spare" cycled sponge to swap into a new or hospital tank. There are a ton of benefits. 

But I don't do it because I only have so many sponge filters, only so many air drops, etc.

So while awesome in a lot of ways, not so awesome that I feel it is critical to do so. I keep 3-4 "spare" sponge filters in a 40B with my shellies so already have that part covered and the circulation difference isn't a big enough deal to me to lose any sleep over.

My 2 cents,
Ken

[Paul]

I run two filters in my 20L but only 1 of them is a sponge the other is a Penguin 175 pro hob. I like having the hob for mechanical/polishing filtration. The combination provides good flow throughout the tank and very clear water. 

Edited November 21, 2020 by Paul