Lotus Aquateck UV Quartz Sleeve O-Ring Sets

Lotus Aquateck UV Quartz Sleeve O-Ring Sets

These replacement O-ring sets are for the quartz sleeve assemblies in compatible Lotus and Aquateck pond UV equipment. They are small service components, but they help form the seal around the quartz tube. Choose the small or large set to match the original assembly and its parts reference, rather than judging the seal by your pond’s volume or the outside size of the filter.

We list the two supplier references together so you can compare the available options without searching through unrelated seals. Small is Oasis reference FL531 and large is FL533. These are O-ring sets only: a quartz sleeve, UV lamp, compression fitting and electrical assembly are not included. A seal that looks close in size is not necessarily interchangeable with the original.

Choose the correct set

Option	Oasis reference	Application
Small	FL531	Compatible small Lotus/Aquateck quartz sleeve sealing assembly
Large	FL533	Compatible large Lotus/Aquateck quartz sleeve sealing assembly

Check the model label, the existing seal arrangement and the original instruction manual before choosing. Similar names have been used across different generations of pond filters, and the overall wattage is not a universal seal specification. Keep the old components until the replacements have been compared and the equipment is working correctly.

If you are buying other parts at the same time, record the lamp, sleeve and seal references separately. A filter can need a new lamp without needing a new sleeve, and a damaged sleeve can require attention even when its lamp still works. Identifying the individual component avoids ordering a complete UV assembly unnecessarily.

When to inspect the O-rings

Inspect the seals whenever the quartz sleeve is removed for the maintenance described in your filter’s manual. Look for cuts, splits, distortion or a seal that no longer sits properly in its groove. Dirt trapped against the sealing surfaces also needs attention. Do not assume that tightening the retaining fitting harder will correct a damaged or misplaced O-ring.

A leak is a reason to stop and inspect the assembly, not to keep running the UV unit while trying different tightening positions. Water around electrical equipment must be treated seriously. Isolate the supply and follow the manufacturer’s troubleshooting instructions; a replacement seal will not repair cracked housings, damaged threads or a fractured quartz tube.

Prepare a clean working area

Disconnect the relevant equipment from the electrical supply before opening the UV housing. Follow the exact unit’s instructions for stopping the water flow, draining where necessary and gaining access to the sleeve. Never operate an exposed UV-C lamp or look directly at it. Allow access space so that the glass can be withdrawn without catching on nearby pipework.

Lay the removed parts on a clean surface in their assembly order. A photograph taken during dismantling can be useful when checking which fitting or seal belongs at each end. Keep electrical components dry and protect the quartz from knocks. The sleeve is brittle, so avoid using it as a handle or resting heavier fittings against it.

Replacing the seals

The Lotus Green Genie instructions describe removing the retaining fittings and O-rings to access the quartz, then inspecting the components before reassembly. Use your own model’s instructions for the precise sequence. Do not assume that a different generation opens in the same way, or that its fittings can be pulled off without first releasing the retaining parts.

Clean the sealing surfaces using the method permitted by the manufacturer, removing debris without scratching the quartz or its housing. Fit each replacement in its intended position without twisting, stretching it unnecessarily or trapping it under a fitting. Use a lubricant only if the equipment instructions specify a suitable type; household oils and improvised sealants are not substitutes for the correct part.

Stop if the new seal will not sit naturally, the fitting will not close as expected or the glass appears different from the original. Forcing an assembly together can damage several components at once. Recheck the model and parts reference before continuing, particularly when more than one filter is being serviced at the same time.

Checks before returning the UV to use

Complete the manufacturer’s reassembly and leak-check procedure before restoring normal operation. Make sure the housing and electrical connections are dry and that all protective covers are back in place. If leakage continues, isolate the equipment again and inspect the wider assembly rather than repeatedly tightening the same fitting.

Keep a note of the service date and the replacement reference with the filter instructions. This makes the next service easier and helps distinguish a recurring seal problem from a separate issue with the sleeve, housing or water circuit. Store any unused spare seals cleanly and away from conditions that could damage them.

Related UV equipment and spare parts

For lamp replacement, browse our pond UV bulbs and match the connector, dimensions and wattage to your existing equipment. For a complete system, compare our pond UV clarifiers against the manufacturer’s flow and pond-size guidance.

If the whole filter is due for replacement, the Lotus Green Genie 24000 with 25W UVC is an example of a complete filter rather than a service seal. Choose a complete unit for the pond, fish load and water flow; an O-ring’s small or large label provides no pond-sizing information.