Geiserailie 15 Pieces Aquarium Filter Media Bags 150 Micrometer Fine Filter Bags Mesh Reusable with Zipper for Activated Carbon Resins(2.4 x 4 Inch,Nylon)

Definitely value for money. It's a little bigger than I needed but performs as I expected. It's durable and can be used for extended period of time without damage or loss in performance.

These bags breathe well, can hold a decent amount, are made of nylon and don’t obscure the contents. This makes the cycle of drying out whatever you need to dry (3D printing filament, in my case), to seeing the dessicant change color if you’re using color indicating dessixant, to throwing the bag in the oven to dry out again easy. I haven’t discovered the temperature these bags stop being able to tolerate the heat, but most nylons can handle the 250°F / 125°C for a quick dry, and definitely the 190°F my dehydrator maxes out at, so I’m not too worried they won’t handle it. My main concern was that the mesh is a good size to not let the smallest silica beads fall out, while not being so fine that there is not enough free air flow to be effective.Not quite the use they were intended (100% wet water vs <15% wet air!) but for those looking for good nylon mesh bags for drying out their 3D printing filament or gun safe or whatever it is, the larger size here will easily hold a pound of silica.

-Good size for my aquaclear 30gal HOB filter. Works great with carbon and similarly sized or smaller media. Would work fine with large media but a larger hole mess would be better for flow. Also a great value. -Biggest pro is they even work great with my purigen resin media without leaking the media out. Also survived the bleach/regen process. -Only complaint is the zipper doesn't open very wide so filling can be quite messy without a funnel. But otherwise works perfectly. And they could be about an inch longer to maximize filtration for my size filter but I imagine it's this size to fit a wider range of filter brands. So not that big of a deal. So far they're the best I've found for my application.

Quick disclaimer - I'm using these bags for small amounts of purigen for my nano aquarium and they work good for that purpose, but I'm not 100% certain they are chlorine bleach resistant so keep that in mind if you plan to re-charge the purigen.Each bag can comfortably hold about 30-40ml of purigen, so I bought the 100ml Purigen bag and was able to split that up into 4 of these Geiserailie bags. The zipper closes just barely tight enough that the purigen granules aren't escaping but to be safe I wouldn't place the bag in with the zipper side down. Overall these bags work great for fine media but make sure you check the dimensions of the bags you're purchasing because the ones I got are way too small for any media larger than Purigen.

These bags are great to run fine media like purigen for fishtanks.I can even bleach purigen in these bags many many times.Which means these bags are tough.The zipper feature is a plus too.I don't use any other bags aside from these.

My ph was low so I wanted to add crushed coral to raise it a bit. These bags are the perfect size to add to my Aqueon QuietFlow 20 (along with a bag of Purigen to keep the tannins out & water clear). They’re strong, and zip well!

Ideal for purigen or charcoal for aquarium filters.

I used purigen in these bags and I had beads getting loose. The zipper doesn’t close tight.

I use for adding purigen to my aquarium filter. Perfect size. Use a funnel and scoop to get purigen into bag

Recomendado para el uso de purigen

En algunos reviews no les gustó el espacio libre del cierre para poder meter el material. A mí me pareció una ventaja puesto que lo usé para Purigen y Matrix. Buen espacio para filtros de nano acuarios de 8-10 galones

Ordered wrong size but amazing bags. Works for Seachem Purigen

No me gusta la malla y son demasiado pequeñas difícil hasta meter el producto. Lo único bueno es que tienen cierre