Acrylic Tank Cracks from vibration?

[100 Gallon Reef]

Has anyone had cracks form on the face of an acrylic tank from heavy vibration or earthquakes? I have a 100 gallon acrylic tank 60x18x22 that formed hundreds of horizontal cracks on the front face during 2 weeks of construction near by. The sewer in the street was replaced less than 30 feet away 15 feet deep they dug a hole and filled it with gravel packing it with a hydraulic impactor on a large escavator. Pictures fell off walls and items fell from tables and shelves and lights swung. The tank sloshed for 2 weeks off and on for hours at a time and cracks up to 1" long formed in vertical rows and patches (see attached pictures). The construction company admits to the heavy vibration, but tells me the cracks that formed in my tank are a coincidence and not caused by the vibration and shaking they do admit to. They told me this is crazing caused by having a 3/8 and not 1/2 inch thick tank? Has anyone ever had damage caused to a tank from earthquake like vibrations?

 

[neilanh]

Seems a little scary to me that you still have water in that tank

 

[Krypt]

If the cracks did not appear until they began ground pounding, then it is definitely their fault. It doesn't matter what the thickness was. If the vibrations they admit to caused your tank to crack, I would definitely contact them again and ask them to replace it. If they do not, then there is always small claims court and home owners insurance.

 

[abdhalim2]

hohoho....scary2 with that crack and your tacnk thickness....

 

[Kurt_Nelson]

Seems to me you have a legitimate claim on the contractor's bond - too coincidental for those to show up in what appears to be a fairly well established tank. If they were doing work on the sewer, I'd contact the owner of the project (the City or Water District?) and fill them on the problem. Perhaps going through them instead of the contractor may help to get some action rather than blanket denial.

Have you contacted a LFS that also does tank work/commercial installations and maintenance, and see what their opinion is? Seems like that would be a good "unbiased" opinion to present to the contractor and project owner. Saltwater City in Bellevue and Barrier Reef Aquariums in Renton come to mind.

 

[100 Gallon Reef]

Thanks all for your replies. I contacted the city and was referred to the contractor's claims manager who now stated they will pay for 1/2 the replacement cost but still thinks it was not caused by them? I gave him the contact information for the LFS who stated this damage is caused by the sloshing of the water causing stress cracks at the weakest point of the tank and is not crazing from age that is seen at the joints, bends, and tops. He replied there is nothing on the web stating damage to acrylic tanks can be caused by vibration. He stated he would pay to replace it if I had more information showing this could be caused by vibration. This is why I was asking for your help as the subject matter expects on this forum. Has anyone herd of this kind of damage.

 

[abdhalim2]

maybe u could get some acrylic manufacturer/expertise advice...

 

[Kurt_Nelson]

100g reef... PM sent to you with contact info of a local acrylic tank fabricator. I'm thinking he can give you more technical info that you can present to the claims manager. I've never heard of damage like you're seeing, but water sloshing in the tank for a couple days isn't something that happens very often!

 

[Innovator]

Considering they were using a hydraulic impactor, it doesn't surprise me regardless of how well made the tank is. You may have luck contacting the manufacturer, but I don't think this would qualify as poor manufacturing due to outside interference of integrity.