How to aviod bubbles in silicone when building an aquarium?

[Mr. Microscope]

Hello All,

I left the hobby about five years ago, but have recently gotten the reefing bug and am thinking about building a new tank. I've build a glass sump in the past, but this time it will be the display tank. So, I really want to make sure everything is done right. I've watched plenty of videos about building glass aquariums from scratch, but none of them explain how to avoid air bubbles in the silicone while assembling the tank. Does anyone have suggestions or techniques? Please, share your experience. Thank you!

 

[SaltwaterGuruNeeded]

Maybe a vacuum chamber. But silicone air bubbles aren't really an issue. I mean if they are big enough for water to get through, I'd see a problem, maybe but you could just fill it in. Just make sure you have a new tube of silicone. I would Only recommend silicone that says "Safe for use on aquariums" because one time I tried to build a sump, tried to save a few bucks and got silicone from home Depot. Waited 2 weeks for it to dry and then fired it up. Killed my fish. I was devastated. Oh and try to run a consistent bead!

 

[Mr. Microscope]

Maybe a vacuum chamber. But silicone air bubbles aren't really an issue. I mean if they are big enough for water to get through, I'd see a problem, maybe but you could just fill it in. Just make sure you have a new tube of silicone. I would Only recommend silicone that says "Safe for use on aquariums" because one time I tried to build a sump, tried to save a few bucks and got silicone from home Depot. Waited 2 weeks for it to dry and then fired it up. Killed my fish. I was devastated. Oh and try to run a consistent bead!

Thank you for chiming in! For filling in bubbles, syringe with silicone?

Yes, I have some reef safe silicone, but might end up buying black stuff from BRS.

 

[Mr. Microscope]

Maybe a vacuum chamber. But silicone air bubbles aren't really an issue. I mean if they are big enough for water to get through, I'd see a problem, maybe but you could just fill it in. Just make sure you have a new tube of silicone. I would Only recommend silicone that says "Safe for use on aquariums" because one time I tried to build a sump, tried to save a few bucks and got silicone from home Depot. Waited 2 weeks for it to dry and then fired it up. Killed my fish. I was devastated. Oh and try to run a consistent bead!

Also, what do you mean by vacuum chamber? I'm talking about bubbles between the glass.

 

[SaltwaterGuruNeeded]

Also, what do you mean by vacuum chamber? I'm talking about bubbles between the glass.

I doubt you have one, let alone one big enough. It sucks all the air out basically like outer space. So the bubbles get so big that they pop, the when I let the pressure back in whatever bubbles aren't popped shrink back down, if any. The extreme pressure makes the bubbles come out and once you let the pressure back in you will have bubble free silicone or as close as you can.

 

[Mr. Microscope]

I doubt you have one, let alone one big enough. It sucks all the air out basically like outer space. So the bubbles get so big that they pop, the when I let the pressure back in whatever bubbles aren't popped shrink back down, if any. The extreme pressure makes the bubbles come out and once you let the pressure back in you will have bubble free silicone or as close as you can.

Okay. Yes, I understood that. Just wondering where on earth I can find a vacuum chamber that is big enough to fit a four foot tank! lol! That was my initial confusion. Thanks again! Cheers!

 

[Lost in the Sauce]

Ime, I've only got an air bubbles in the silicone when there was a break in the bead being applied. If you can go slow with your silicone bead application to ensure you have a clean line, there should be no bubbling.

One trick I have used to fill in a gap caused by the above was applying a glob of silicone to the inside after some dry time and holding a shop vac to the bottom side in order to suck silicone down through the void. This worked flawlessly for me the only time I've tried it.

If you have an air compressor, one great way to get clean beads and something that maybe worth the investment is to purchase a pneumatic application tool. I used to use them when installing car windshields. It looks the same as a normal caulking gun but has an airline run up to it with a regulator. You dial the regulator up or down to the desired amount of flow. When you hit the trigger, you get a constant flow constant speed the silicone bead without having to stop and pump it more with your hand.

Good luck on this endeavor, I wish more people would make their own tanks so we can get a bigger list of pro tips out there.

 

[Mr. Microscope]

Ime, I've only got an air bubbles in the silicone when there was a break in the bead being applied. If you can go slow with your silicone bead application to ensure you have a clean line, there should be no bubbling.

One trick I have used to fill in a gap caused by the above was applying a glob of silicone to the inside after some dry time and holding a shop vac to the bottom side in order to suck silicone down through the void. This worked flawlessly for me the only time I've tried it.

If you have an air compressor, one great way to get clean beads and something that maybe worth the investment is to purchase a pneumatic application tool. I used to use them when installing car windshields. It looks the same as a normal caulking gun but has an airline run up to it with a regulator. You dial the regulator up or down to the desired amount of flow. When you hit the trigger, you get a constant flow constant speed the silicone bead without having to stop and pump it more with your hand.

Good luck on this endeavor, I wish more people would make their own tanks so we can get a bigger list of pro tips out there.

Thank you! Those are some great tips! I've seen a video with someone using one of those pneumatic tools to build aquariums. He did one in like a minute (and it looked something like 50 gallons!). I couldn't believe it. Really impressive to see one of these in action with an experienced hand.

 

[Lost in the Sauce]

Thank you! Those are some great tips! I've seen a video with someone using one of those pneumatic tools to build aquariums. He did one in like a minute (and it looked something like 50 gallons!). I couldn't believe it. Really impressive to see one of these in action with an experienced hand.

They are a great investment. Mine came off of the snap on truck but I'm sure there are many other manufacturers making them for a lot cheaper.

If your go that route, do a few test beads with the exact silicone you will be using for the project at the same temp. Both will change the flow rate slightly.