Cracked bottom

I bought a tank from a local reef group member and the bottom is cracked from the bulk head to corner of the over flow. Was wondering if I should scrap the tank or do something to try and repair. I haven’t even put water in it do to buying all the equipment for this exact tank.
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I honestly couldn't sleep with that. Moreover, I don't even know of a product I'd trust to 100% seal that. Sadly, silocone isn't as strong as a weld.
 
It’s a rimless 60G cube, I was wondering if it would be okay but there was salt deep on the crack underside. I contacted the previous owner that bought it 9 months early and he stated that the bulk heads were leaking but stopped when he tightened them.

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So he knew it was cracked and didn’t tell you? Hopefully you paid with PayPal and can get a refund. That’s bad business...
 
Unfortunately I bought locally with cash , out 300. Not a crazy amount but still very inconsiderate.

There's no way to be sure they did or didn't know. I'd contact them and see, explain that a closer inspection shows a crack, the crack is filled with salt meaning it was cracked while it was still wet.

Though I admit, a personal sale is cash and carry as-is. It's not right, but that's the risk in buying used.
 
There's no way to be sure they did or didn't know. I'd contact them and see, explain that a closer inspection shows a crack, the crack is filled with salt meaning it was cracked while it was still wet.

Though I admit, a personal sale is cash and carry as-is. It's not right, but that's the risk in buying used.


If you unscrew the plumbing and even clean it, there’s no way you didn’t see that. That’s not a scratch, that’s a three inch crack.
 
I've had a tank leak from the bottom before. That turned into three days of hell, tons of coral loss, and the loss of a couple of fish, and it set me back by several months towards getting a new tank. And that was with a simple leaking seam; with an actual crack that could give out and cause a truly catastrophic leak, that tank would be a ticking time bomb.

If you're confident in your silicone work, you may be able to get a replacement pane for the bottom and re-seam the tank. Personally, unless it's a large tank that's expensive to buy new, I'd just get a new tank.

Amen!

Been there. Don’t incur the risk if it can be avoided.
 
Obtain two bulkhead plugs and clean up tank and sell it as a reptile tank and take proceeds from sale and apply to purchase of a replacement tank
 
Looks like someone left the bulkhead on and moved the tank while the weight was on it. that tank would make a great reptile tank.... that's about it. sorry bud
 
Wow... this an interesting dilemma

The crack is in the overflow section sooooo by physics you wouldnt think a whole lot of weight (waterwise) would put that much pressure on the crack. an overflow probably only holds maybe 5-10gals of water (?)...times 8lbs/gal equals maybe 50-100lbs of water weight (?). Not much PSI being forced on that crack IMO.

The crack has already made is way to the edge and it has no where else to spread to.

So think about this! What is the WORSE that would happen? I extremely doubt the whole bottom would explode outward downward. The crack AINT going to reverse and spread across the bottom in the opposite direction.

I think the worse would be the crack just leaks like a mother.

Begs to question: do you have a SECOND OVERFLOW in the other corner? If so there has to be a way to cut off water overflowing this chamber and just use the other overflow.

If I were you I would di this:

1) see if you can contact a USA based Mfgr of tanks as see if you can talk with a "Tank Structural Engineer". Were all hobbyist even this Structural Engineer and you might be surprised what advice they give for free

2) research off R2R on ways to repair cracks to glass. Bonding chemicals...bonding methods.....to repair its ability to hold water.

3) I'd select the BEST repair option an put the tank in the garage or basement where if the whole thing completely lost all the water like BOOM.... that cleanup would be easy. I would test it with only water (no fish, etc) and stress test it for a month watching for how much water its leaking, dripping, wetting, etc.

4) I definitely wouldnt just dumpster the tank. IMO the crack has completed its failure Journey to the edge... the weight of water in that chamber is not the same PSI on the glass OUTSIDE the overflow.

Anyone else thinking the way I'm thinking?



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I am a glassblower by trade and happen to know of a glue that is stronger than the glass it fixes. You would need to clean it very well and seal the crack completely with this two part stuff. Since it is in the overflow you might be able to get away with the repair, but I would run it in a spill safe spot for a while before using it in a display area.
I still agree with most of t he other post that it is best to repurpose or scrap. Just wanted to offer a viable option
 
definitely wouldnt just dumpster the tank. IMO the crack has completed its failure Journey to the edge... the weight of water in that chamber is not the same PSI on the glass OUTSIDE the overflow.

I agree with the first two points, not so sure about the third ... pressure is a function of water column height not total water mass, though I suppose the water level in the overflow is lightly lower. Best advice probably is to dump the tank, though as I noted back in page 1, I would probably explore fixes before tossing it. That there was evidence of salt creep on the outside of the crack suggests it wasn’t actively leaking or that the glass was shifting. My guess is that the crack was a consequence of over torquing the bulkhead. I’d patch it an run somewhere for a while where failure wouldn’t do any damage.
 

IF YOU HAD TO TAKE A REEFING EXAM, WOULD YOU PASS?

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  • Not yet, but I have one that I want to buy in mind!

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  • No.

    Votes: 26 37.1%
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