Express Water RO systems use standard filter sizes, giving you flexibility on where to source replacements. Here's what you need and where to find it.
| Stage 1: PP Sediment | 10" × 2.5", 5-micron — wide compatibility |
| Stage 2: GAC Carbon | 10" × 2.5" granular activated carbon |
| Stage 3: Carbon Block | 10" × 2.5" CTO carbon block |
| Stage 4: RO Membrane | 50 GPD compatible membrane — check model |
| Stage 5: Post-Carbon | Inline post-carbon, standard connection |
The pre-filter and carbon stages are 10" × 2.5" standard cartridges — one of the most common sizes in the water filter industry. iSpring, APEC, Watts, and many other brands make compatible replacements. This competition keeps prices low.