leak on 300g acrylic tank

[goldenboy]

Wow, seems like forever since I've been here. College kinda ate away at all of my free time.

Today I bought a 300g reef ready acrylic aquarium from a guy on Craig's list for a mere $100. It's got lots of scratches from rocks and according to the owner, claw marks from a large savannah monitor that used to be housed in it. Nothing too terrible that it won't polish out (I hope/think). Anyway, I bought a 3 part acrylic polish called Novus at my LFS. Is there anything else that I can do to make sure that the tank polishes up nicely?

Now onto the bad part. I went to fill up the tank to test it's water holding ability and it turns out that there is a 7" separation between the bottom and back panel that just pours the water out of the tank. I inspected all of the other panels and everything else appears to be in good shape. All of the panels are roughly 1/2" thick BTW. Haven't measured them yet so I could be slightly off.

My other concern is that the back panel is made up of 2 pieces of roughly 1/4" blue acrylic sandwiched together to make a 1/2 panel. Could this be part of the reason for the separation on that panel. The 2 sandwiched pieces appear to be bonded together very well, it's just the back where the bottom and back panel fit together.

So anyway, I am loosely familiar with the process of bonding acrylic together though I have never done it myself. How should I go about patching this back panel? Or is it even an option? If not I will just silicone the seem and turn it into a huge poison dart frog display (my other pet hobby). In all honesty though, I would much rather fix the tank so I can either upgrade my reef or put together a predator tank with some morays, grouper, lionfish etc. Please let me know what my options are. Thanks

 

[Anonymous]

goldenboy wrote:

I went to fill up the tank to test it's water holding ability and it turns out that there is a 7" separation between the bottom and back panel that just pours the water out of the tank.

A 7" separation? And you didn't see that before hand? Really?

Can you elaborate on this leak? Surely it's not really a 7" separation.

A picture would be immensely helpful.

Louey

 

[Acrylics]

While it very well may be fixable, my worry would be that the joint could either separate again or some other joint could separate. Many folks don't want to spend the $$ on good material, esp in colors so they use (IMO) garbage material and piece it together. Many times this material doesn't want to glue well by normal means and joint separation is not an unusual occurance. Not saying this was necessarily the situation in your case but would definitely not be the first time I've heard of such. With that said, I'd do my best to fix it with a gusset and use it for the frogs or sell it, but that's just me.

The Novus set will only take out minor scratches and hazing. For deeper scratches either sand & buff it out or sand it out and use Micro-Mesh to clean it up. Either way can be time consuming and you may earn the money you saved

FWIW, Micro-Mesh can be found at www.micro-surface.com kit #NC-78-1 is a good hobby grade kit that contains everything the master kit (MA-1) does but in smaller pieces.

James

 

[goldenboy]

Thanks for the help guys

A 7" separation? And you didn't see that before hand? Really?

Can you elaborate on this leak? Surely it's not really a 7" separation.

A picture would be immensely helpful.

Louey

Sorry, I see where your confused. What I meant by that was that there is 7 inches along the back where the seem is separated from the back and bottom panel; but the gap that it creates is not even enough to slide a piece of paper through so it is next to impossible to see. You only notice it when there is water in the tank and it begins to leak. I can get pics if need be.

Is there anyway that I could fit a piece into the bottom along the length of the back. to patch it? The only problem would be that it would have to be 2-3 pieces because of the cross support on the top of the tank.

 

[Acrylics]

Cross support at the bottom of the tank? not at all normal for acrylic tanks...hmm
You could put gussets in there though I'd use Weld-on 40 rather than any solvent.

James

 

[goldenboy]

Cross support at the bottom of the tank? not at all normal for acrylic tanks...hmm
You could put gussets in there though I'd use Weld-on 40 rather than any solvent.

James

Doh! somehow where missing each other hear What I mean is the cross support on the top (Not bottom) of the tank would prevent me from putting a new piece along the entire length of the back, bottom of the tank. You know how large acrylic tanks have a piece of acrylic on the top with two openings cut out and then there is a piece of acrylic in between the two openings.

Here's a pic of what I mean buy crossbar. The acrylic piece in between the two maintenance openings.

Here's a pic of the scratches. There's lots of em, but none of them are really gouged or deep. Some of what you see in the pic is just grime and dirt on the acrylic.

Here's the leak at the bottom back of the tank. You can see the water pouring out of the seem.

Is there any point in fixing this for fish? I guess what I am saying is, if done correctly should a gusset and some weldon, or some other fix hold this separation in the seem? Let it be known that I Paul Sewell will not hold anyone liable for any future leaks in the aquarium. And that I am solely responsible for the quality of the repair of this aquarium. Sorry, I realize that people are reluctant to give an answer that may end up not working, but I need as straight of an answer as possible. I just want to know if it's worth trying or if I will just end up wasting my time and money.

 

[Acrylics]

Ah, I see, sorry for the confusion, some day I'll learn to read
IMO the gusset(s) installed with liberally applied Weld-on 40 would work as well as anything. You could also just turn the tank on an angle so the back corner is down (front up) and just flood that area with 40. There used to be a tank mfr than built tanks like this, still might be around - not sure. Either way, cost isn't much - maybe $20-40 depending on how much you get. A 4 or 8oz ($10 or so) kit will provide enough for the gusset(s), a quart would prolly provide enough to flood the area well enough.
It could be made to be "sea-worthy" but my personal concern is still regarding the other joints. If you are comfortable with them, then give it a shot. Be sure to do this and water test it prior to cleaning up the rest of it too much just in case it doesn't work as well as one would hope and you will not have wasted too much time.

HTH,
James

 

[goldenboy]

alright cool, Thanks for the help James. I'll try it out and leave it filled up on the porch for a month or so to see how it does. I won't be using it immediately anyway. Funds are a little low right now. :roll:

 

[goldenboy]

BTW, could you define exactly what you mean by gusset in terms of an aquarium?

 

[Anonymous]

Here is what I feel, FWIW.

1, Looking at the first pic with the cross bar, you should be able to slide in a 8ft long 1/2 inch square rod. What you can do is that it can be used to reinforce the joint on the back side.

2, I concur with James that this is not a very good tank to work on, but the price is right. There is a reason that it is a lizard tank, and that is usually abuse or bad construction or leak. I would inspect all the seams carefully even if I buy an existing tank with water in there. That's because I have been burnt before

3, If you are getting the micromesh, you may need to spend a couple days of polishing it if you do it by hand. Practice it on a scratch before going crazy on the real thing.

 

[Acrylics]

A gusset, in terms of aquariums, would be a 1 x 1" (or so) strip of acrylic (sometimes triangular but not necessary here) that is glued on the inside of the joint such that it bonds equally to the horizontal (bottom) and vertical (back) pieces.
Given that solvent didn't bond well to begin with, I'd use the Weld-on 40. It's a thick syrupy solution that is an acrylic resin. It is a 2-part solution consisting of a monomer and catalyst similar to an epoxy but it's actually acrylic. If you're interested in this, it can be purchased from most plastics distributors. It may have to be ordered though as it has a shelf life so not often stocked.

HTH,
James

 

[Anonymous]

>...IMO the gusset(s) installed with liberally applied Weld-on 40 would work as well as anything. You could also just turn the tank on an angle so the back corner is down (front up) and just flood that area with 40. There used to be a tank mfr than built tanks like this, still might be around - not sure.

I think there is a shop (down in San Diego?) that build tank with gusset reinforcement, but I never see one myself. Triangular gusset needed to be ordered, but square rod can be readily made from scrap if you can finish the cut properly. Am I right?

 

[Acrylics]

Triangular gusset needed to be ordered, but square rod can be readily made from scrap if you can finish the cut properly. Am I right?

You can make the triangular yourself just as easily. Just route an edge on the material and then cut on a tablesaw at 45deg angle and you now have the gusset

James

 

[Anonymous]

Why didn't I think of that? It will be nice to have two 135 degree angles instead of two 90 and one 270. Much easier to clean and looks better.

 

[goldenboy]

Hey, Thanks for all the great help guys. I think that what I will do is reinforce the length of all the top and bottom joints with square gussets. Then I will reinforce the 4 vertical joints with triangular joints up to the top of the tank (since they will be the most visible) effectively framing in all of the joints inside of the tank.

My reasoning for doing the top and bottom of the tank with square gussets would be that:

1. They won't be seen very easily because of the DSB and canopy.

2. I wont have to cut additional angles on the ends of the vertical triangle gussets to get them to match up to the top and bottom gussets. Thereby, relieving a lot of headaches and potential errors in the cuts.

Also, I think that this will make sure that any other unknown stressed areas in the joints wont end up springing leaks. I imagine that I could probably get all the pieces I need from scrap acrylic and save myself some cash.

What do you all think?

 

[Acrylics]

Perfectly reasonable to me

James

 

[goldenboy]

Was just looking at square and triangle rods on US plastics site. they sell them by the foot in 6' sections. since my tank is 8' would it work to have a 6' piece and a 2' piece to stretch across the long joints of the tank? or would the 2 pieces compromise the strength of the gusset?

Also, They only make the triangle rods in 3/4". could I go with 1/2" square rods and 3/4" triangle rods? or would I just be shooting myself in the foot? Going with 1" really, really increases the cost; although I am willing to take the hit if I really need to.

Here's the breakdown"

3/4" tri and 1"square rods $209.58

3/4" tri and 3/4" square rods $128.10

3/4" tri and 1/5" Square rods 66.36

So you can easily see how huge the cost difference is. What should I do?

 

[Acrylics]

Just use all 3/4" triangle, it'll be as good as anything else. If you have a Tap Plastics or other plastic shop in your area, take a look there too, pricing is a little less.
One caveat though, these shapes are not square by any means nor are the sides flat. Shouldn't matter if using Weld-on 40 but if you are going to use solvent - can make it tough. Kinda why I mentioned making them yourself if possible

And no, you won't be compromising strength to any large degree by using smaller pcs.

James

 

[Anonymous]

Yeah, they are extruded acrylic, and the supposingly flat surface is concave in most cases. Some even have bubble trapped in them, probably not a big issue. I often have extra scrap laying around so I usually make them myself. I may get the triangluar one from the shop, so that I don't have to borrow a table saw from my neighbor.

There is no problem with using multiple pieces.

 

[goldenboy]

Alright, thanks guys! I will check around locally to see what I can do and then use weldon 40 to adhere the gussets. From my reading it appears as though the weldon 40 is probably the easiest to use for a beginner in acrylic working. Like I said earlier, I have never worked with acrylic before but I do have quite a bit of experience doing tons of other DIY stuff; so I am confident that I can do it.

Edit:
I'll also look into making them myself from scrap. Thanks again!