Help! Cracked acrylic tank on new setup. How do I repair?

[ramoer]

Hi All,

I bought a tank off CL a while ago and just set it up. It has a small 1" crack on the top brace that is coming down the front of the tank. The crack doesnt go all the way through and is above the water line. This is really worrying me, I have already spent alot of money to get this up and running on supplies etc, I dont really want to have to start all over. Is there any solutions? (excuse the cloudy water, I just added sand).

Top View http://i1138.photobucket.com/albums/n528/ramoer/photo2-2.jpg

Front View
http://i1138.photobucket.com/albums/n528/ramoer/photo1-2.jpg

[Steveb]

I'm no expert but I would put a lot of money on the "yes its a problem side".

You might read through this thread for some ideas...

www.reefcentral.com/forums/showthread.php?t=1056956&highlight=acrylic

Try contacting Acrylics (James) or Floyd R Turbo via PM here on RC.

[sfsuphysics]

first thing I'd do is put a brace on it perpendicular to the direction of the crack, like a "quick clamp" or similar type, this will let you figure out what to do without it getting too much worse.

Then slap a piece of thick acrylic ontop of it similar to a bandaid, use a liquidy type of weldon hopefully that wicks into into your crack and plugs any leaking. Won't look pretty but it'll work

[StaghornE]

X2. If you scab another piece if acrylic over the crack with the correct weld on that will stop the crack. I did this with silicone and a piece of glass on a glass tank. With zero problems.

[immokalee98]

I would do this quickly. the water in the tank is only added stress to that area.

[Dapg8gt]

I'd also say that's is a problem. You never know if that crack is gonna take off. I would think the only way would b to put a piece over it like said above. I wouldn't use silicone you would need weld on #3 for it. I would try to get a piece long enough to go across the entire span so it doesn't look to bad. Won't look super good but IMO better than a piece just stuck over it. JMO

[Acrylics]

you will want to drill a small hole at the end of the crack and then patch over it. However you will get drips and more ugliness by not having it glue on a horizontal plane. You will still have an ugly patch anyway the patch should extent a little beyond the crack in all directions.

Caveat, due to the fact that your tank was flame polished, you run the very real risk of crazing when you glue the patch on. Crazing is fractures in the material due to stress.

My personal thought is to take it down, scrap this tank or use it as a sump and get a good tank. You will have to look at that for years. You don't have any animals in there yet. This is the time to do it.Sorry this happened, but taking everything into account for the life of the tank (years) this would be my best advice.

James

[Gorgok]

If you are handy with woodworking and plan to make a canopy you could ugly-patch it and have the canopy hide it. My canopy extends just below the water line as is anyway...

But, i would take the whole tank down, emptying it and all, then fix it with the tank sitting in a way it can't run down further. Its fine if it runs up towards the bracing, so a slight lean in that direction would be my goal.

[ramoer]

Thanks for all the help/advice. I am in an area that has had 2 moderate earthquakes in the past week so it is a bit urgent. I am planning on doing my first major water change this weekend, and I will drill hole, and use some weld on 16 to patch up this crack. I will eventually build a hood that should cover the patch.

[adambowersva]

Hey ramoer, James has given you the hard, but best advice. I am an acrylic tank builder in VA and I'm sure James would concur with his even greater wealth of experience that Weld-On 16 isn't likely going to hack it.

It's recommended that you use Weld-On 3 or Weld-On 4 for this. 16 just doesn't have as much holding strength as the others do.

I would second the use it as a sump motion.

[chris s]

Third vote for using it as a sump.

It will hurt to buy a new tank now. But how much will it hurt later if you have an established tank end up all over the floor?

Another option is to find someone to buy it for a reptile tank.

[nolken]

4th vote for sump. It would not be fun to try and repair a further crack once your fish are in there. You could drill a hole and repair that like James mentioned, however, as he mentioned, you are at a very high risk of crazing since it is so close to the flame polished edge. Weld-On 16 only has 12% less final bonding strength than Weld-On 3 or 4. The main concern for Weld-On 16 is it takes a much longer to go from 80% to 100% bond strength and greater risk of bubbling.

[MJB Tanks]

Look at it this way, you may have a lot of money in it now...but you can't replace time. What if 2 years down the road you have killer corals and mature fish and the tank gives way and you lose everything.

I run from acrylic repairs. I'll go with the sump vote here too, I just so happen to be making a sump out of a failed 90g tank myself :)

[hebygb]

I believe that early on in this thread there was a misinterpretation of what a "patch" would consist of. When a patch was suggested it was not to try and fill in the crack, but to laminate the area surrounding and over the crack with a second piece of acrylic. This done in conjunction with the drilling at the end to prevent the crack from continuing. That is why it was suggested that a canopy could conceal the flaw.

Despite clarifying this, I do agree with several that this tank should be repurposed.

I am a huge fan of acrylic tanks... All of mine are. If mine showed any sort of crack like this I would have to say a replacement is the route I would take.

[Floyd R Turbo]

That tank will probably not last 2 months without proper repair to that crack. Do it right. Do what James said, empty the tank, drill a hole to stop the crack (don't even think about drilling that hole with the tank full) then patch over both sides. If it crazes, it's toast and good for a sump only, but right now it's toast anyways IMO.

[ramoer]

I am considering taking down the tank and selling out the parts... My water has already cycled but I am worried about the crack growing, so I have the options

A. Try to repair with some weld on 4 and acrylic patch with water still in the tank (If I empty it, I might as well just give up)
B. Take the tank down and sell off my skimmer rock etc.

This is disappointing but it could be worse if that crack grows. What do you guys think?

[Steveb]

Why are you so hesitant to take the water out of it? Do the repair right. Its really no big deal to drain it. Get you some trash cans from the HW store and drain the saltwater into them. If you have rock or what not put that into the containers as well. Put a couple power heads in for circulation.

[dwolson2]

Why are you so hesitant to take the water out of it? Do the repair right. Its really no big deal to drain it. Get you some trash cans from the HW store and drain the saltwater into them. If you have rock or what not put that into the containers as well. Put a couple power heads in for circulation.

Like he said, better to do it right then be fighting with it for a longer period of time.

I also think you may want to scrap it and use it as material for your sump(which is what I did with a 180, which now I have a very nice custom sump;) )

[hebygb]

removing the water, or at least most of it will not affect your tank as much as you think. most of the biology is in the sand (if there is any) and the rock. But even the biology in the rocks can be salvaged about 75 - 80% by doing as posted above (trash cans).

The patch area needs to be clean and dry ... but you can do this easily when the tank is near empty. Curing time is minimal... a few days at best.

The only downside to fixing this tank is that you will have a patch presumably in the top of the front pane, But as mentioned above, you can conceal this with a deeply lipped hood.

Replacing the roock and water back in the tank is easy and you may experience a small cycle here or there, but that happens to everyone on RC that upgrades a tank, moves stuff around, or a million other chemistry issues.

Enjoy the tank.

[ramoer]

Found a local plastic repair shop that sells weld-on 4 and acrylic scraps. Do you guys recommend also rebracing the top of the tank since the front seems to be bowing outward?

[Sonny n Colleen]

The front pane is bowing from the pressure exerted by the water and with an existing crack you are flirting with disaster. The crack is a stress concentration point and stop drilling/repairing it is only a temporary fix. What bothers me is the brace and the front pane appears to be cracked. Tank integrity may already be compromised if both are cracked. It could take minutes or milliseconds for the crack to grow and the tank fail. I recommend you take the tank down ASAP and go the trash can route baringcs suggested. There is a post on here where a huge acrylic tank in a casino failed suddenly without warning, dumping thousands of gallons of water in a matter of seconds.

[icex2010]

http://www.reefcentral.com/forums/showthread.php?t=2209709&highlight=casino

[cbonito]

I vote abandon ship.
There is no way I would attempt to salvage a cracked acrylic tank unless the tank itself was very large and a sizeable investment.

Then again, I would still likely abandon it anyway knowing what could happen during that process, and to fix it RIGHT it needs to be taken down ANYWAY.

Any risk of a tank dumping all over the floor in my livingroom is an unacceptable risk.
It's cheaper to replace the tank than the floor, and the furniture, and your wife when she leaves and moves in with her parents.

This is likely something you dont want to hear, but that's why you need to hear it.
The cold hard facts are speaking to you and you're trying to convince yourself otherwise.
Take it down and spare yourself the grief...please.

[Steveb]

I would trim it down and put new bracing on it and use it as a big ole frag tank my second option would be sump/refugium. I just can't stand the thought of not trying to salvage it. But I do agree I would not want to dump a boat load of saltwater, fish, corals, sand and maybe rock on the floor. Your lucky if your wife moved out (relatively speaking), mine would kick me and all of my toys to the curb (muttering under her breath the whole time) LOL...

[tomservo]

If you do choose to patch it, you definitely need to drain it first.. Welding a non-stressed piece of material to a piece with stress in it is a bad idea with any kind of material.

[ramoer]

I have decided to take it down and part it out. Patching is just gonna be a headache and may not be a permanent solution, plus I have a new condo with nice wood floors, the risk is too high. Thanks for all your advice/opinions. I think Ill take a break from this hobby for a while...

[Acrylics]

I have decided to take it down and part it out. Patching is just gonna be a headache and may not be a permanent solution, plus I have a new condo with nice wood floors, the risk is too high. Thanks for all your advice/opinions. I think Ill take a break from this hobby for a while...
what are/were the dimensions of the tank?

[ravi197699]

X2. If you scab another piece if acrylic over the crack with the correct weld on that will stop the crack. I did this with silicone and a piece of glass on a glass tank. With zero problems.

i agree with him try to put piece of acrylic on top of the crack and use the right cement and it will be good fix

[ramoer]

its a 110G tall, 60 x 18 x 24. Its my mistake, I purchased the tank off CL and thought I could make it work. The original owner must have cut away some of the top bracing to make the openings bigger, this pretty much ruined the tank.

[cbonito]

its a 110G tall, 60 x 18 x 24. Its my mistake, I purchased the tank off CL and thought I could make it work. The original owner must have cut away some of the top bracing to make the openings bigger, this pretty much ruined the tank.

You're not alone!
I've made my share of CL Mistakes as well. lol

Hopefully this didnt set you too far back. That just stinks.

[Sonny n Colleen]

I wouldn't give completely up. Do what baringcs suggested. Find someone who can cut acrylic and shorten the tank a inch or two below the crack and fit a new top brace. Plus there is always a CL deal to be had. Good luck!