How much Seachem Matrix

[FishyFishFish]

I have set up a QT and am using Seachem Matrix as the filter, in place of rock/sand.

The instructions say to use 250ml of Matrix for every 200 litres, which is about 5oz of Matrix per 50 US gallons.

My QT is obviously a lot smaller than 50 US gallons, but how does anyone know how they calculate an amount of about 1oz per 10 US gallons (which is very little). Is this supposed to be the amount to use instead of rock/sand or in addition to? If the latter, was does the Matrix do that rock doesn't do?

I looking at my bare QT with its tiny amount of Matrix in there (twice the recommended amount), wondering if it will ever cycle!

 

[jtp7004ft]

My understanding was that matrix just gives you more surface area for filtration than live rock. The more that you put in might effect the cycling process, kinda like starting your cycling process with dry rock.

 

[Azedenkae]

Is this supposed to be the amount to use instead of rock/sand or in addition to? If the latter, was does the Matrix do that rock doesn't do?

Instead of rock/sand, and because these media has a lot more surface area to volume ratio than live rock. Allegedly.

I am cycling my 2.65 gal and was dubious too, because theoretically I'd need at least 2.65lb live rock.

I use 72 MarinePure gems instead, which are super small and defo weigh nowhere near 2.65lb. And nitrification seems to be happening fine.

 

[FishyFishFish]

Instead of rock/sand, and because these media has a lot more surface area to volume ratio than live rock. Allegedly.

I am cycling my 2.65 gal and was dubious too, because theoretically I'd need at least 2.65lb live rock.

I use 72 MarinePure gems instead, which are super small and defo weigh nowhere near 2.65lb. And nitrification seems to be happening fine.

That makes sense; it just looks odd.

If you work to a rule of 1lb of (dry) rock per US gallon, that would required 10 lbs of rock in a 10 gallon tank. According to the Seachem instructions you only need 1oz of Matrix in the same size tank to achieve the same result. That is a huge difference.

The instructions also compare it to plastic bio balls and, according to Seachem, this 1oz of Matrix is equivalent to 8.5 litres of plastic balls!

If these numbers are correct then this really is good stuff. It's also pretty cheap (~$1.20/oz) so is ideal for a QT as it can be used and then just thrown away afterwards. The rocks are also big enough to fit in my filter without a filter bag (but still small) so one less thing to worry about.

I'll continue cycling with what I have in there and see what happens.

 

[Beau_B]

I use mesh tie-top media bags. Each might hold a cup (.25L)? I never measured, just dumped it in the bag. It doesn't absorb the copper/metro/prazi, so I even rinse and dry the media out after a QT use and then re-cycle in the sump. It does change color in NFG so I toss that stuff assuming it absorbs something.

No ammonia issues in 10g with a single bag in a HOB.

Most recently I discovered it makes great burrow material for jawfish. I had lost one in QT because he stopped eating and I equated it to being uncomfortable. This time I emptied a bag of matrix on the bottom against some PVC and he's built a burrow with it. Happy as a clam.