hi can you tell me can you use red scoria as media in a sump tank cheers

Yeah. Why couldn't you?

don't expect it to hold much bacteria .

Why not, Discusguru? It's extremely porus. My local pet shop uses it in their CFS, it does the job well

Hell of a lot more surface area than bioballs...

It doesn't work for me when I was using it for my sump (4 ft) servicing 4 4ft tank. Keep getting ammonia spike.

Replace it with Eheim media and no more ammonia and nitrite in the water. Water change and feeding routine stay the same.

Base on my experience.

Cheers,

Ronnie

I have used it in cannister filters and it seemed to work fine, however I would use it as a last resort, i.e. if finances just dont allow you to buy proper media. There are two reason for this, 1) proper media IS better, it is made/designed specifically for the job. 2) when natural rock like this is formed (includes pumice to) it can (often?) have other stuff mixed in with it, metals, other types of possibly reactive rock etc. This can be seen clearly in pumice by the different coloured lumps if you saw a piece in half.

I have used it,

I used bio balls in my trickle tower, and scoria in my sump as a way of adding more surface area, it does work but can clog up.

Its good if you want extra surface, but i preffer bio balls.

Nylon pot scrubbers have a huge surface area - more than bioballs and scoria. Totally inert, and water flow is probably very good through them.

Im gonna use these in my cannister when I get it going. They are cheap too!