Scratched Glass

[Reefer5640]

I thought I would share my experience with this and hope someone else can benefit from it as I have. I bought a used 120 Gal reef ready tank to start a new build for way cheap last summer. It had some pretty good scratches in it but I figured I could get them out myself and save a bunch of money. Not knowing what I got myself into I found there are a lot of debates on wether you can even get scratches out of glass. I tried a bunch of the DIY/home remedies; baking soda paste, tooth paste, metal compound... and non of them did much at all. So I went online and did more research and found an option that looked promising. I ordered a powder compound called cerium oxide and some felt pads for my drill and grinder. It took hard water and calcium buildup off no problem and it actually took off a bunch of little superficial scratches. The stuff works pretty good for scratches that you can’t catch you finger nail in. It will take out the scratches that sometimes accumulate from old mag cleaners and scrapers. But it doesn’t touch the scratches that you would deem a tank trashed over. The ones that a peice of sand gets stuck between the glass and the mag, the ones that are the only thing you can focus on... I was about to give up and sell the tank when I stumbled across this new process where they grinde the surface off and refinish it. It’s called glass renu. There’s a video on YouTube you can check out. I tried to buy the stuff from their website but they don’t sell it to the public. They gave me the name of a company that provides the service. I called them up and they were awesome! It actually got these super deep scratches out. The glass looks brand new. I’m stoked this worked out and I don’t have to ditch the tank. I’m going to start a build thread soon. Here are some before and after pics. They’re not the same angle or background but they are the same scratches, hopefully you can see in the first pic how bad they were...

 

[zack801]

Hello fellow Utahn! I can’t really tell anything from the before and after pics but if you got out the scratches you wanted to then that’s awesome!

 

[Reef Jeff]

I use cerium oxide to remove scratches too. I found it when restoring classic car glass and like you said, it works great on aquarium glass. I don’t care for the felt pads as they can be too aggressive and if the edge catches the glasss just right it can leave scuff marks. I use automotive paint buffing foam pads as they don’t do that. It’s a lot of work to remove light scratches from glass, but sure beats buying a new tank. Glad it worked for you too!

 

[medic17]

i bought this 75 gallon tank 2 weeks ago I bought the cerium oxide powder along with some courses pads and polishing pads I am going to be using a corded drill for this procedure. Any tips y’all can give. There are a few scratches that u can catch ur nail on but most are superficial.

 

[Reef Jeff]

i bought this 75 gallon tank 2 weeks ago I bought the cerium oxide powder along with some courses pads and polishing pads I am going to be using a corded drill for this procedure. Any tips y’all can give. There are a few scratches that u can catch ur nail on but most are superficial.

Don’t use corded drill. You should use a variable speed buffer and run the speed between 600-1000 rpms. When you start hitting 1200 rpms on aquarium glass it gets hot and will mar. The corded drill will not allow you to control the pad flat enough and will cause more scratches. You can get a good cheap variable speed buffer at Harbor Freight for this job. Keep the surface WET at ALL times and frequently rinse the pad and glass and keep applying more wet clean cerium oxide paste. Keep the pad moving at all times. Also, ANY dirt that gets under the pad will further scratch the surface. Everything must be extremely clean and dirt/grit free. Plan to spend 4-6 hours buffing. Mine took 12 hours. It is not a fun job. The scratches that you can feel will not be removed by this process. That requires special equipment and skill.

 

[cincyfishguy]

What was the cost to have them buff them out? Did you take the tank to them or did they come to you??

 

[medic17]

Don’t use corded drill. You should use a variable speed buffer and run the speed between 600-1000 rpms. When you start hitting 1200 rpms on aquarium glass it gets hot and will mar. The corded drill will not allow you to control the pad flat enough and will cause more scratches. You can get a good cheap variable speed buffer at Harbor Freight for this job. Keep the surface WET at ALL times and frequently rinse the pad and glass and keep applying more wet clean cerium oxide paste. Keep the pad moving at all times. Also, ANY dirt that gets under the pad will further scratch the surface. Everything must be extremely clean and dirt/grit free. Plan to spend 4-6 hours buffing. Mine took 12 hours. It is not a fun job. The scratches that you can feel will not be removed by this process. That requires special equipment and skill.

What type of buffer pad do I need

 

[Reef Jeff]

So I went online and did more research and found an option that looked promising. I ordered a powder compound called cerium oxide and some felt pads for my drill and grinder. It took hard water and calcium buildup off no problem and it actually took off a bunch of little superficial scratches. The stuff works pretty good for scratches that you can’t catch you finger nail in. It will take out the scratches that sometimes accumulate from old mag cleaners and scrapers. But it doesn’t touch the scratches that you would deem a tank trashed over. The ones that a peice of sand gets stuck between the glass and the mag, the ones that are the only thing you can focus on... I was about to give up and sell the tank when I stumbled across this new process where they grinde the surface off and refinish it. It’s called glass renu. There’s a video on YouTube you can check out. I tried to buy the stuff from their website but they don’t sell it to the public. They gave me the name of a company that provides the service. I called them up and they were awesome! It actually got these super deep scratches out. The glass looks brand new. I’m stoked this worked out and I don’t have to ditch the tank. I’m going to start a build thread soon. Here are some before and after pics. They’re not the same angle or background but they are the same scratches, hopefully you can see in the first pic how bad they were...

When you say they grind and refinish, I assume they buff to refinish? Just curious if they use a coating of some kind or just grind the surface a few thousandths and buff.

 

[Reef Jeff]

What type of buffer pad do I need

Foam automotive buffing pad. 4” or 6” works well for an aquarium. 6” would work best for 75 gallon tank.

 

[medic17]

When you say they grind and refinish, I assume they buff to refinish? Just curious if they use a coating of some kind or just grind the surface a few thousandths and buff.

Ok so I found a variable speed buffer at Home Depot for 54 and already have the cerium oxide just need to know if there is a specific pad I need to use and I take it I should buy a few of the pads

 

[Reefer5640]

What was the cost to have them buff them out? Did you take the tank to them or did they come to you??

They came to the house. I offered to take it to him but they wanted to do it at the house. They said it was the same cost either way. It was $150 minimum they did not exceed that. They said that usually covers the sqft of a sliding door so you could do a pretty big tank if that’s the case. Obviously would t be worth it on the smaller tanks but to buy my tank used without scratches was double that so it worked out beneficial for me.

i bought this 75 gallon tank 2 weeks ago I bought the cerium oxide powder along with some courses pads and polishing pads I am going to be using a corded drill for this procedure. Any tips y’all can give. There are a few scratches that u can catch ur nail on but most are superficial.

+1 on what reef Jeff said. I’ve tried every tool I have; dremel, drill, angle grinder, oscillating multi tool, car buffer... You need the control of a variable speed, it’s a must... As far as the scratches you can catch your nail on, unfortunately it can’t get that deep. It can definitely help and maybe they’ll be at more tolerable level after the cerium oxide but as far as getting rid of them all together, not likely... As far as the pads, I used all felt with every tool and I can say if you’re not careful like reef Jeff mentioned you will cause scuffing and more work for yourself. I also used Terri cloth on my car buffer and that helped quite a bit for the end polish. Never did try the foam buffing pads though. I’m definitely going to.

When you say they grind and refinish, I assume they buff to refinish? Just curious if they use a coating of some kind or just grind the surface a few thousandths and buff.

Its all a dry process, yes they take it down a few thousandths. The glass looks terrible after that step. They work their way back up finer and finer and finish with cerium oxide.

 

[Reef Jeff]

Its all a dry process, yes they take it down a few thousandths. The glass looks terrible after that step. They work their way back up finer and finer and finish with cerium oxide.

Nice... I was not aware of a company that could plane the glass a few thousandths and buff back to a new shine. That’s a great service for what you paid.

 

[pwfish]

I wish I would have know that prior to using cerium oxide, got the small scratches out but not the deep ones. Have had the tank going for a year now and wished I had just purchased a new tank. Not going to change it out now as cost over $400 just to have it moved into my basement.

 

[medic17]

I wish I would have know that prior to using cerium oxide, got the small scratches out but not the deep ones. Have had the tank going for a year now and wished I had just purchased a new tank. Not going to change it out now as cost over $400 just to have it moved into my basement.

Yes I am calling glass companies Monday to see what they are going to charge

 

[Reefer5640]

Yes I am calling glass companies Monday to see what they are going to charge

If you can’t find anyone I emailed glass renu to get contacts of companies that offer they’re service in my area. They got back to me the next business day

 

[Hal3134]

I spent 4 hours buffing a 2ft by 1 ft side of my tank with cerium oxide and no noticeable improvement. I have etching from coralline algae.

 

[medic17]

I spent 4 hours buffing a 2ft by 1 ft side of my tank with cerium oxide and no noticeable improvement. I have etching from coralline algae.

Glad I found another 75 gallon tank for 200