Leaks / Gasket Issues

Troubleshooting Gasket Leaks

Please watch this video to see how to properly install the Shadow onto your aquarium to prevent leaks.

Gasket Leaking:

  • Are the gaskets aligned correctly?

    1. The gaskets need to be centered over the holes in the tank to seal properly. If they are not centered they can get pulled into the hole when tightening the bulkhead causing small drips or leaks.

    2. Watch the video "Installation onto an aquarium" for proper alignment of the gaskets.

  • Check that the bulkhead nuts are securely tightened. DO NOT Overtighten with any tools or wrenches. The gaskets were designed to be sealed with hand force only and may leak if overtightened.

  • Check the holes in the aquarium:

    1. Are they the correct size (63-65mm)? We recommend using 63mm holesaw for the best seal. 64mm or 65mm will take a little more effort to make sure the hole is covered properly with the gasket.

    2. Is there and scalloping or chips in the holes of the class/acrylic? The holes need to be clean and chip free for the best seal.

  • Is the glass or acrylic clean where the gaskets need to seal?

    1. Is there paint or other material on the aquarium surface? Remove any paint or debris from the area. Gasket on Glass/Acrylic are going to give the best seal.

    2. Clean with Isopropyl Alcohol (glass only) and reseat the gaskets.

  • Is the plumbing secured?

    1. Make sure that the Rear Box PVC pipes are secured to the aquarium stand and not just hanging below the box. This will cause the overflow to not seal properly on the gaskets. The pipes when full of water will be very heavy and will pull down on the rear box causing the gaskets to unseal.

    2. We recommend the Quick Clips we use in our installation video for the best way to secure the pipes properly.

    3. Pipes need to be secured as close to the external overflow box as possible.

  • Hand Tighten the bulkhead nuts ONLY. Do NOT use any tools to tighten the bulkhead nuts. Overtightening can cause leaks to happen by over compressing the gaskets.

For systems that have been setup for extended periods:

  • If a small drip has formed over time, it can also be caused by any of the above mentioned issues. We also recommend the following procedure:

    1. Drain the aquarium to a level below the 2 drilled holes in the back glass/acrylic.

    2. Remove the bulkhead nuts and take the front weir box out of the aquarium.

    3. Remove the rear box at the Unions if you use them.

    4. Remove all 4 bulkhead gaskets and soak them in a solution of warm water and mild dish soap for about 30 mins. THe Gaskets are made from a TPO material that will never need replacing. Unless there is a major defect in the gaskets, they will last forever when properly cared for.

    5. Use warm water and a mild dish soap with a cloth and thoroughly clean the area where the overflow was connected to the rear of the aquarium.

    6. Proceed to then follow the steps above for "Gasket Leaking"

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