Ceramic bio media

[Khole new fish]

Question my fish tanks are nano and have small filters I was wondering if I can place the ceramic bio media on the substrate or does it have to be in the filter??????

[redmare]

There's no reason you couldn't but bio media on the substrate, it will grow bacteria anywhere it's coming in contact with water. If your tanks are already stable and running with whatever media you have though, I wouldn't feel the need to add to it or swap it around. Why are you wanting to add additional media?

[Khole new fish]

I was just wondering and want to be informed about this things, I have like three or four piece in each filter and they are going good.

[HH Morant]

Beneficial bacteria needs both surface area and flow. Little of a tank's BB is in the substrate because of a lack of significant flow. Under-gravel filters or powerheads directed at the substrate can create the needed flow, but most aquariums do not have them.

I highly recommend the articles on filtration at aquariumscience.org (spoiler - the author does not think much of ceramic filter media). Surface area inside micro-pores in filter media is not useful because there can be no flow through them. Sellers of filter media hype this surface area, which actually serves no purpose.

[Guppysnail]

I’m with @HH Morant it doesn’t get better than 30 ppi sponge foam unless you up to k1 fluidized media. Ceramic rings and bio media read the fine print fluval biomax fine print states to replace every 6 months. Sponge is made of a type of plastic never clogs never needs replaced. There is no flow through all the pores in ceramic rings except the center hole and once gunk is on the surface it’s no more porous than gravel. I actually gave them a try just to see what the hype was about and sorry but I’ll keep my 30 ppi which it also gives some mechanical filtration as well almost never clogs has much more surface are for bacteria and I need to clean it much less often. 
to your original question YES it can be laid on the ground I have done it to seed tanks (what I did with the batch I tried and did not like) but it’s just like gravel no better. 

Edited December 8, 2021 by Guppysnail

[lefty o]

On 12/8/2021 at 9:48 AM, Guppysnail said:

I’m with @HH Morant it doesn’t get better than 30 ppi sponge foam unless you up to k1 fluidized media. Ceramic rings and bio media read the fine print fluval biomax fine print states to replace every 6 months. Sponge is made of a type of plastic never clogs never needs replaced. There is no flow through all the pores in ceramic rings except the center hole and once gunk is on the surface it’s no more porous than gravel. I actually gave them a try just to see what the hype was about and sorry but I’ll keep my 30 ppi which it also gives some mechanical filtration as well almost never clogs has much more surface are for bacteria and I need to clean it much less often. 
to your original question YES it can be laid on the ground I have done it to seed tanks (what I did with the batch I tried and did not like) but it’s just like gravel no better. 

ill add on to this. though a manufacturer states to replace ceramic media every six months, there is no reason to do so. they tell you to replace, simply so that they can sell you more. ceramic media gives a place for bacteria to grow, it doesnt get used up. im not much of a ceramic media person, but if you have it, use it.