Fluval Top Cover O-Ring

Fluval Top Cover O-Ring

Compatibility

Setup & Use

What it is, precisely. This is the Filter Lid O-ring (item 12 on Fluval’s own FX-series parts diagram), part A20210: shared between the FX4 and FX6, while the smaller FX2 uses a different part (A20213). It’s a separate part from the "Top Cover Click-Fit O-rings" (a 4-pack of small o-rings sealing the AquaStop valve connections on the same lid). This listing is the single large ring that seals the lid itself to the canister.

Fitting it. Per Fluval’s own FX manual, inspect the filter lid O-ring for wear whenever the lid comes off for cleaning, and reseat it before closing the lid back onto the canister. There’s only one correct orientation. Fluval doesn’t put this O-ring on a fixed replacement calendar the way it does the impeller or motor seal; replace it once it’s visibly worn, cracked, or no longer sealing without a leak.

Returns & Replacement

Returns are accepted within 7 days of delivery, provided the item is unused and in its original packaging. Manufacturer-sealed items cannot be returned once the seal is broken, and sale-priced items are not refundable.

If your item arrives defective or damaged, message us on WhatsApp with your order number, or email us if you would rather, and we will replace it. Approved replacements are delivered within 3 to 5 business days. Transit damage is covered by insurance on every shipment. If tracking shows delivered but nothing reached you, tell us within 48 hours, which is the reporting window Indian couriers allow. Damage caused during installation or use is not covered; replacement spares for such cases are chargeable.

Full terms are on our Cancellation & Returns page.