First i agree with comments above on the scratch...Not so much on the holes , But I have to wonder about a few things,
Do you have Contract with this person to build the tank for you, If so on this contract does it talk about Conditions of the tank, Delivery inspection and time frame for notifying them.
How was this tank delivered and by who. If shipped what does the packaging look like..
Now for the LAW Part. Its a Custom made product , Here in the us your rights are not the same as if you buy something off the shelf at a store, The company has a right to CURE The issues with the Product,, Being they could send a local glass company out to buff out the scratch and bulkhead holes , This would make you whole again.
Also what is there warranty...
I would give them the benefit of the doubt and request they send someone for a local glass shop to fix the tank.Give you a LIFETIME Warranty against glass breakage at the BULKHEADS and a Discount on the price for your Inconvenience ...
If they refuse the above then for sure they need to take the tank back. With that said i almost bet they have a Policy to make you whole but will not accept returns..
I know because the nature of my business we have customers who ask for specific things , When we are done they decide they do not like is . Such as paint color or type of tile or design. This is why we have at Sign off on plans and images of what we are going to do before we do it..
The tank can be the same thing if it was truly "CUSTOM BUILT" for you. If they refuse you can also get a local glass company to come out and repair it and sue them for the cost of repairs.but only after the tank builder refused to make you WHOLE..
The above is why 2 days after i complete any project or a area of a large project i get the Customer to sign off on it. This limits My liability in case they break it after the fact but even then i almost always Repair it for free. Unless i find the Customer went out trying to get restitution before working with my company to resolve the issue..
I own a Home Renovation Company.. my business is not always cut and dry, The tank should be but because of the word CUSTOM. That makes it not a NEW Tank but i built product....
Just my opinion from the other side of a Product provider. Yes he is liable to make you whole. Replacing the tank.I Do not think so if he can make you whole.. .I will add one more thing. If this is a ONE MAN SHOP . He should have notified you about the bulkhead chip and sanded it out himself and included bulkheads that would not be compromised .. The scratch could have just been messed...
Asking you to make any repairs yourself makes me feel this is common for his business... I have drove 20 miles across town to clean finger prints off a window that one of my guys where in to big of a hurry to do... I WOULD NEVER Ask a customer to fix even something minor them self..
I will stop typing now........ I am sure i will get a lot of flack from people on here for my OPINION.. This is JUST How it is Legally