What to Do If an Acrylic Fish Tank Leaks — Can It Be Repaired?

Many people panic the first time they discover their acrylic fish tank leaking: How could such thick acrylic leak? Can it even be fixed?
In fact, most leakage issues aren’t caused by the material itself, but by problems at the joints or improper use.

The biggest difference between an acrylic tank and a glass one lies in how they’re assembled. Acrylic tanks use a solvent welding technique, which means the panels are actually fused together, unlike glass tanks that are held together with silicone — which can peel off over time. Generally, a high-quality acrylic tank built to proper standards is almost leak-proof. However, if the bonding is uneven during installation, if the tank experiences long-term uneven pressure, or if it’s exposed to drastic temperature changes, tiny cracks may still form at the seams.

If you notice a leak, the first step is to stop using the tank and drain it immediately. Do not continue running it. Next, carefully inspect where the leak is coming from — is it a surface crack or seepage from a seam?
For minor leaks, you can use a professional acrylic repair solvent or adhesive to refill the gap. Once it cures, sanding and polishing can restore a nearly invisible, clear finish.
If the crack is deeper or covers a larger area, it’s best to have a professional team re-bond or replace the damaged panels.

It’s worth noting that acrylic is highly repairable, which is one of its major advantages over glass. While a glass tank usually has to be discarded once it cracks, acrylic can often be restored to like-new condition through polishing, reinforcement, and re-welding.

So, don’t panic if your acrylic tank starts leaking — the key is to identify the cause and get the right help. With quality materials, proper bonding, and regular maintenance, your acrylic tank can continue to safely hold your little “ocean” for years to come.