Seachem Matrix Bio Media 250ml

The bio-medium is little volcanic-type rocks, large pea size. I’m using about half the container (250ml, so about 125ml). I’ve put the rocks into a bag, purchased separately, that fits my filter. My tank is 15 gallons and my filter runs at 200 gallons an hour (sounds crazy) so the rocks get a lot of flow. When I switched to this brand, I left my old bio-medium in the tank for about a week, so the bacteria would populate the new medium. My ammonia and nitrite are running at zero. I rinse the bag of rocks about once a week, scrubbing it between my hands to clear the algae. The rocks don’t get clogged, so I haven’t had to change them out for fresh ones. It takes time to build the bacteria population, and it’s important to keep something in your aquarium where the little creatures can live. In the photo, I’ve layered a bag of eggshells on top of the Matrix. (The eggshells raise the pH.)

I love this product! It really works to eliminate ammonia, nitrates and nitrites! I have seen a remarkable improvement in my tanks water quality since implementing this product into my HOB filter!

The amount of media you get for the price is just ridiculous. Seachem seems to be getting greedier every year.

I like this stuff, its versatile and the pieces are a good size.

Excelente me llegó rápido es un frasco que contiene 250ml, ya lo tengo funcionando en mi pecera

Best media for planted tanks

Works as advertised. Would recommend it.

I had a problem with my ammonia levels. I tried several things to bring it down, to no avail. I bought matrix and after a few days my ammonia levels are back to 0. I now will never use anything else. Best in the world.

Matrix is the best biomedia out there, imo. I use it on my 5 gal planted betta tank. Lots of surface area due to its porous composition (lots of microscope images on Google), and you can pack a bunch of it into a small space. The pieces are about the size of small grapes, and with a little rinse to get rid of the dust, you pop em into your filter and forget about them until maintenance. I have 250mL of Matrix sitting in the back of my Fluval Spec V in a nylon media bag under the sponge that came with the tank. I have been fishless cycling for a few weeks, and my tank holds enough bacteria to easily process 3-4 PPM of ammonia in well under 24 hrs. Matrix works, and being a biomedia, it doesnt get easier or better than this. For all you Spec V and Spec III owners out there, I use this with the stock sponge (cut a bit off to shorten), stock ceramic media, and a 100mL bag of Purigen, and it keeps my water filtered and crystal clear.

great product