Cracked tank during drilling... silicone?

pluikens · May 5, 2018

Hey all,

So I was drilling a couple tanks that I'll be using for filtration purposes, I got to the last hole of the evening and managed to cause a crack in the glass. The tank is a 40 breeder with only one 1" hole in this end for a return from the sump. With the position of the hole and where the crack occurred, I'm thinking of applying silicon over the crack to the inside after applying the bulkhead. What are everyone's thoughts? Should I apply the silicone on the inside before installing the bulkhead so some silicone gets between the glass and gasket? Do I need to apply silicone to the outside? My thinking was if water is getting between the inside silicone and through the crack during tests, I would get another tank and try drilling again. The tank is on cement in my basement fish room so some drips would be ok during tests as I would then replace the tank.

And here's a picture of the tanks on their stands before I drilled them. System recirculates up from the 125-gallon round sump tank holding live rock into the 40 breeder refugium, overflows to the 20 long for my internal skimmer, then back to the sump. Reef, FOWLR, and frag tanks have their own return pumps out of the sump.

ZachR32 · May 5, 2018

Wouldn't trust it so close to the corners

pluikens · May 5, 2018

ZachR32 said:
Wouldn't trust it so close to the corners

Interesting. My thought was that being close to the corner would help the matter since it can't spread further and the corner silicone is helping hold it. Are you thinking the glass in the upper left corner of the end panel would fail out? My holes for the overflow out of this tank aren't any higher and I won't be using an overflow box so I don't expect the waterline to be much higher than the bottom of the hole with the crack.

rtparty · May 5, 2018

I'm far from qualified to give an expert opinion but for $55, I would get a new tank. There is no reason to risk a disaster that could flood your house and crash your tanks because of $55

samnaz · May 5, 2018

+1 too close. The length between the edge of the tank and the edge of the hole should be equal to the diameter of the hole, or larger.

I def would not risk it if I were you, not worth it.

User · May 5, 2018

samnaz said:
+1 too close. The length between the edge of the tank and the edge of the hole should be equal to the diameter of the hole, or larger.

I def would not risk it if I were you, not worth it.

This.

Distance to any edge should be at least 1x diameter of the hole. I aim for 1.25x.

The hole you drilled was too close, hence the crack. If you have others in similarly close to edge locations, it’s more a matter of when, rather than if, they will also fail.

Sorry, but I’d buy a new tank and redrill. Hopefully you can find a use for this one.

miPapareef · May 5, 2018

An issue to worry about is the mechanical strength of the cracked class to hold your bulkhead and plumbing and the force of water and wave action in the tank. I think the issue is much more about mechanical strength than can you seal a crack. There are a lot of forces trying to crack that glass and because of the water force on the glass any new cracks will not be limited to the corner.

Coralfuture · May 5, 2018

I wouldn’t trust it as all have been saying. I would go get a new tank and use current one for baffles. Petco does their 1$ per gallon sale all the time and you can get that tank for 40$ there. Saves a little money at least.

User · May 5, 2018

Dollar/ gallon sale literally finished last Sunday. It’ll be s couple months before it’s back.

pluikens · May 5, 2018

neilp2006 said:
Dollar/ gallon sale literally finished last Sunday. It’ll be s couple months before it’s back.

I know, that's when I bought these.

User · May 5, 2018

In that case, your lucky it wasn’t worse...

Petco 29g side panel is tempered!!
https://www.reef2reef.com/index.php?threads/Petco-29g-side-panel-is-tempered!!.385116/

Aqueon tanks for petco don’t have a consistent glass type for their panels. Depends upon availability at the time they are assembled. Poor product QC in my view.

pluikens · May 5, 2018

Thanks for the responses, everyone. I'm quite disappointed with myself. Not about the money because it's not much at all, but about the waste. I've drilled tanks before successfully/properly, I even thought to myself "maybe I should watch some of the youtube videos before starting this" yesterday. I even wasted a bit of time trying to decide where to drill! If I had known the minimum distance to the edge guideline, I would have just measured 1.25" from the edge of the panel and put it there! Ugh, thanks again, everyone!

User · May 5, 2018

How big was the hole? 1.25” isn’t always going to be dough. I aim for 1.25x the diameter, although 1x is good.

I put the bit at the edge of the panel, estimate another 1/4 (basically half the distance between the edge of the bit and the stem for the chuck) mark it and make that the closest I’ll put the hole.

pluikens · May 5, 2018

neilp2006 said:
How big was the hole? 1.25” isn’t always going to be dough. I aim for 1.25x the diameter, although 1x is good.

I put the bit at the edge of the panel, estimate another 1/4 (basically half the distance between the edge of the bit and the stem for the chuck) mark it and make that the closest I’ll put the hole.

It was a 1" hole, that's why I said 1.25".

The 20 long I drilled has the holes a minimum of 1.125" inches from the panel edge so that's salvageable.

User · May 5, 2018

That works. Yeah, the 20l will be fine.

Good luck on the next one!

pluikens · May 5, 2018

neilp2006 said:
That works. Yeah, the 20l will be fine.

Good luck on the next one!

You too!

rtparty · May 6, 2018

Coralfuture said:
I wouldn’t trust it as all have been saying. I would go get a new tank and use current one for baffles. Petco does their 1$ per gallon sale all the time and you can get that tank for 40$ there. Saves a little money at least.

As a heads up, the 40B is no longer on the $1/gallon sale (at least not in my area.) It is now one of the 50% off sizes. The dollar per gallon ends at the 29G now. Anything larger is now 50% off. Still a great deal for a 40B or 75G though.

pluikens · May 8, 2018

I bought a new 40 breeder on Sunday. The cracked one will go under my 4' x 2' frag tank stand to store propagation and cleaning tools. I don't work Wednesdays so I have all day tomorrow to drill the new tank, paint both tanks, and glue the plumbing. If all goes well, I'll have water flowing through the filtration tanks by the end of the day!

T Carey · May 8, 2018

Since this is not a display tank, I would put a 4" x 4" glass patch siliconed over the entire contact surface to seal the hole and proved structural support. I would line the patch up with the edge of the tank. If you feel nervous about it put a patch on both sides. Then I'd turn the tank around 180° and drill a new hole spaced further in from the edge and go on with life. Since you already have a replacement tank it's a moot issue, but you can use that tank as a liquid containing tank if needed by patching.

pluikens · May 8, 2018

T Carey said:
Since this is not a display tank, I would put a 4" x 4" glass patch siliconed over the entire contact surface to seal the hole and proved structural support. I would line the patch up with the edge of the tank. If you feel nervous about it put a patch on both sides. Then I'd turn the tank around 180° and drill a new hole spaced further in from the edge and go on with life. Since you already have a replacement tank it's a moot issue, but you can use that tank as a liquid containing tank if needed by patching.

Might be a good project for me though! I wouldn't mind a 40 Gallon QT for corals or upgrade my fish QT from the current 20 long. Are you suggesting a patch on the inside or outside? If on the inside, do I just push it up against the silicone in the corner and silicone away?