Fluval 07 Motor Head Gasket/ORing 105/106/107 & 205/206/207
Water type
Freshwater + Marine
Fits
Fluval 105, Fluval 205, Fluval 106, Fluval 206, Fluval 107, Fluval 207
Part no.
A20038
Replace every
12 months
In the box
1 x motor head gasket O-ring
Pack quantity
1 motor head gasket
Genuine part
Yes, genuine Fluval
Fluval 07 Motor Head Gasket/ORing 105/106/107 & 205/206/207
One perished seal is all it takes to put water on the cabinet floor.
This is the genuine Fluval motor head gasket, part A20038, the large O-ring that seals the motor head to the canister body. Fluval lists it across three generations of small-body canister – the 105/205, the 106/206 and the 107/207 – which makes it one of the few parts an owner can buy without first working out which generation they have.
Key features
- Genuine Fluval A20038 – moulded to the correct section and diameter, so the head clips down with the right compression instead of being forced.
- Covers three generations – 105/205 (model codes 201 and 206), 106/206 (A202, A207) and 107/207 (A440, A443).
- Fixes the two classic symptoms – a slow weep down the outside of the canister, and a filter that will not hold prime because it is drawing air past the seal rather than water.
- Cheapest insurance in the cabinet – the part that fails is worth a few dollars; the water damage it causes is not.
- Fits in seconds – it sits in a moulded groove and presses home by hand. No tools.
Specifications
| Manufacturer part number | A20038 |
|---|---|
| Sold as | Single gasket |
| Position in filter | Groove in the underside of the motor head, sealing to the canister rim |
| Water type | Freshwater and marine |
| Tools required | None |
Will it fit my filter?
A20038 is the small-body gasket. The large-body canisters use a bigger seal and are not covered by this part.
| Filter | Model code | Takes A20038 |
|---|---|---|
| Fluval 105 | 201 | Yes |
| Fluval 205 | 206 | Yes |
| Fluval 106 | A202 | Yes |
| Fluval 206 | A207 | Yes |
| Fluval 107 | A440 | Yes |
| Fluval 207 | A443 | Yes |
| Fluval 305, 405, 306, 406, 307, 407 | Various | No |
Fluval does not list A20038 for the 305/405, 306/406 or 307/407. Those canisters have a larger head seal listed separately against their own model codes – check the parts list for your model rather than assuming the small-body ring will stretch to fit, because a seal on the wrong compression leaks worse than the perished one you removed.
Which canisters is this for?
The three generations A20038 covers are the two smallest Fluval canisters in each range. These are the current 07 figures, for sizing against a tank.
| Model | Aquarium capacity | Pump output (empty) | Filter circulation (media loaded) | Max head | Power at 240 V |
|---|---|---|---|---|---|
| 107 | 40–130 L | 550 L/h | 360 L/h | 1.45 m | 10 W |
| 207 | 60–220 L | 780 L/h | 460 L/h | 1.45 m | 10 W |
What's included
- 1 x motor head gasket O-ring
Not included
- The AquaStop valve seals. Those are separate, and they are a different leak point higher up.
- Silicone grease. Fluval does not supply it with the gasket.
- The motor head. This is the seal only – see the 107 motor head or the 207 motor head if the head itself has failed.
Suitable for, and not suitable for
Suitable for a canister that weeps at the joint between head and body, one that will not hold prime, and any small-body Fluval that has been opened many times over several years. Also worth fitting as routine on a second-hand filter before it goes near a cabinet.
Not suitable for the 305, 405, 306, 406, 307 or 407, or for the FX Series. It will not stop a leak at the hose connections or at the AquaStop, which are different seals entirely – dry everything and watch where the water actually appears before buying a part.
Care and maintenance
Fluval's own guidance is to keep the gasket clean and lubricated. Wipe the groove and the ring at every service, and use a smear of silicone-based lubricant, never petroleum jelly, which degrades rubber. Replace the ring when it has gone hard, flattened into a permanent oval, or shows any nick along the sealing face. A gasket that has taken a set will seal on the bench and weep once the filter is running under head.
Goes well with
- 107/207 impeller with ceramic shaft (A20109) – the other wear part worth replacing while the head is off
- Ceramic impeller shaft and bushing (A20039) – for a canister that has gone noisy
- 107/207 media basket cover – stops water bypassing the media
- 07 Series primer assembly – if the filter still will not prime after a new gasket
Warranty and delivery
Supplied as a genuine Fluval replacement part. Your rights under the Australian Consumer Law apply in full and nothing here limits them. Fluval does not quote a separate warranty term on rubber service parts. Ships as a standard small parcel anywhere in Australia.
Common questions
Does the Fluval A20038 gasket fit a 307 or 407?
No. Fluval lists A20038 for the 105/205, 106/206 and 107/207 only. The larger canisters use a bigger head seal listed against their own model codes.
How often should the motor head gasket be replaced?
Fluval does not publish a fixed interval. Replace on condition – when the ring has hardened, taken a permanent flat, or nicked. Many owners change it every couple of years as cheap insurance.
My filter leaks a little after every clean. Is the gasket the cause?
Usually it is the gasket, or the gasket seated badly. Check the ring is fully in its groove with no twist, and that nothing – a strand of filter wool is the classic – is trapped across the sealing face.
What lubricant should I use on it?
A silicone-based lubricant only. Petroleum jelly and mineral oils swell and perish the rubber, and a swollen ring will not seat in its groove.
Will one gasket do a 106 and a 107?
The same part number serves both, so a spare on the shelf covers either filter. You need one gasket per canister; they are sold singly.
