Aquarium frame cracked

PghReef · Jan 29, 2018

Not sure if this is the right forum for this post, if not please move to more appropriate one.

I have a marineland 46gal bowfront. Had it set up about 2 years and then upgraded and have had it sitting on it's stand empty for the last 4 years or so. Wife loved the look of the tank so I got it out the other day to give it a once over and fill if with vinager water to test for leaks and give a good cleaning. I knew some of the silicone was in rough shape from algae scrapers but also noticed the top rim is cracked. The center brace is in great shape and intact, it's the actual rim in the back corner. I'm going to contact marineland but doubt they'll do anything as I don't believe these tanks are even in production any longer from them. Is the tank still safe to use? I have it full in the garage just in case and plan on having it sit for a week or so to be sure with filters and powerheads running. Sitting on top of the tank is an old light fixture it is not part of the rim

Also I know you can't silicone over silicone to create a seal, but if the structural silicone is intact would I be able to place a new wider bead from glass pane to glass pane to reinforce and protect the structural silicone in the seam? As you can see it is worn down pretty much all the way to the front pane but never did leak and seems to be holding up fine so far for the leak test.

PghReef · Jan 29, 2018

PghReef · Jan 29, 2018

Awesome Dennis · Jan 29, 2018

The cracked top plastic would make me nervous.

PghReef · Jan 29, 2018

Makes me a little nervous but I'm not sure how much structural support it provides since the center brace is still intact. Do we have an engineers or experts on this forum for tank integrity?

Porpoise Hork · Jan 29, 2018

The top plastic trim adds minimal overall structural support to the tank, but it is cause for some concern. You will want to verify that the tank is perfectly level to ensure the seam will not rupture or crack the glass. You can pick up a leveling mat that will make this task much easier. As for the cracked trim, drain the tank mix up some high strength epoxy and fill in the crack making sure to get some adhesion to the glass under the trim. Once cured you can sand it down and/or paint it if desired.

PghReef · Jan 29, 2018

Porpoise Hork said:
The top plastic trim adds minimal overall structural support to the tank, but it is cause for some concern. You will want to verify that the tank is perfectly level to ensure the seam will not rupture or crack the glass. You can pick up a leveling mat that will make this task much easier. As for the cracked trim, drain the tank mix up some high strength epoxy and fill in the crack making sure to get some adhesion to the glass under the trim. Once cured you can sand it down and/or paint it if desired.

Thanks I was thinking about using some epoxy jusy wasnt sure it would be considered strong enough to make a sound repair.

What about the silicone, as long as no leaks is it ok to apply an additional thicker bead to the corners just for added support and protection for the structural silicone?

Porpoise Hork · Jan 29, 2018

Silicone does not have the same level of adhesion to plastics as it does to glass. As such you can fill the crack with silicone but it will do little to secure the trim and restore the top frame to it's original level of protection like epoxy would. As long as you properly prepare the plastic for the epoxy, there is no better method for repairing this than any decently strong epoxy like liquid JB Weld. Adding additional silicone down the edges, it would be more for peace of mind than actually doing any real benefit to the tank. Do a close visual inspection of the seams to make sure the silicone is not cracked or hardened in any way. As long as it is intact and pliable, (press your fingernail against it and you should see an indention left behind) then there is no need to mess with it.