QuietFlows

10:
- for aquariums up to 20 gallons
- cartridge size: Medium

20:
- for aquariums up to 30 gallons
- cartridge size: Large

30:
- for aquariums up to 45 gallons
- cartridge size: Large

50:
- for aquariums up to 50 gallons
- cartridge size: Large

75:
- for aquariums up to 90 gallons
- cartridge size: Large

We carry the Medium & Large replacement cartridges in both three & six packs.