100 Gallon Tank Questions

[JasReef]

Hello I hope everyone is having a great Saturday!

First, I was hoping someone could share some knowledge on this center brace. It looks to me like it is something that was added after the tank was built but I am not sure. I do know that it cannot stay the way it is, it's a 12 inch piece of glass in the center of the tank, doesn't seem helpful in growing corals as it was caked with salt and crud.

Second, does the glass look tempered? I would like to drill it but I am not sure.

The tank itself is 60x19.5x20.5 inches. The glass seems to be 1/2 inch thick. I believe this tank was made in the 80's. I know the guy I got it from had it up and running since then. He resealed it recently but then he went with a smaller tank so I got it cheap.

Thanks

[jolt]

Large tanks back then were pretty much always made with center braces as far as I recall. I don't think you should run that tank without a brace. It would not cost much to replace it if you want to be certain it's not tempered

[jestep]

1/2" glass might be thick enough to support a rimless setup, but on such an old tank, I don't think I would risk it. On my 48" long tank, which is 1/2" glass, it only bows a few millimeters which is way less than many 36" tanks I've had without center braces.

Most likely the bottom pane is tempered and the rest aren't. It's also possible that none are, or the bottom and the back, but bottom pane is most common. Easiest way to tell is to put a smart phone or laptop screen behind the pane and rotate it. You will typically get major distortion viewing the screen at certain angles with tempered glass. Polarized sunglasses usually work well also.

[JasReef]

Thanks for the replies!

Jestep, I don't want to de rim it, just remove/replace the brace with something more easier to work with.

JimH, Maybe instead of one 12 inch plate of glass have three 4 inch pieces spread out. Or a metal brace all the way around like FarmerTys setup.

Tried the smartphone and laptop trick and see no distortion. I followed along with a couple of youtube videos. Still not sure.

I did remove it and it was not too bad . I can take the center piece to a glass shop and see if they can tell what kind it is.

Also, I found a tag for Ocean View Aquarium products. I can shoot off an email to them and see what they say. I found an old thread from 2009 on Reef Central and the consensus seems to be none of them are tempered. I guess for the money I paid I can just drill it and see.

[jestep]

This could break the tank, but if you want to try brace-less, try filling it up on a level supportive surface outside or somewhere you don't mind getting wet. See how much the front and back bow out. I'd keep an eye on it as you fill it just in case it looks like it's bowing too much. If it's actually half inch glass all around, I still think you'd have a decent shot at keeping it without a brace.

Personally, I think it would be structurally better to just have 2 smaller braces dividing the tank in 3rd's than a single in the middle, if you do decide to keep a brace on it. I don't even think you'd need 3 of them, 2 should be plenty if they're well attached.

[JasReef]

Jestep, that is a good idea. I think it will hold up.

It almost seems to me the brace was put there to hold up the glass tops and not as a structure support. I may fill it up and see tomorrow.

Thanks

[JasReef]

Well, I have decided to put this tank on hold for the moment. I am buying Shalakos 160 gallon set up (minus the frag tank).

Thanks for the help.

If anyone is interested in the 100 gallon let me know. I have it on CL for 100 but will do 75 for anyone on here or I may trade for a good sized return pump. Otherwise maybe I can turn it into my frag tank.