Idea for Faux sand bed. Envirotex Lite high gloss finish.

[docjay]

Really sorry to hear about your loss. Now I've got something to worry about until thursday. My tank is 3/4" so hopefully it won't crack. Was your tank flat on a stand with foam under it or was it a tank with trim on the bottom? Was this the first time you filled it? I'm just grasping at straws here, trying to see my situation as different from yours. I've been working on this tank since May. I'd hate to think all that work and $ could be for nothing.
Time will tell.

Thanks for the warning.

Jay

 

[Brad524]

I am thinking of doing this to a 70 gl. let me know how those turn out
I would hate to crack my tank

so if there's something underneath would it be ok?

 

[hdtvguy]

Really sorry to hear about your loss. Now I've got something to worry about until thursday. My tank is 3/4" so hopefully it won't crack. Was your tank flat on a stand with foam under it or was it a tank with trim on the bottom? Was this the first time you filled it? I'm just grasping at straws here, trying to see my situation as different from yours. I've been working on this tank since May. I'd hate to think all that work and $ could be for nothing.
Time will tell.

Thanks for the warning.

Jay

The tank has been setup for a year before doing this. It is a all glass tank with foam under the stand.

I'm not sure what really causes it to crack? Maybe the cold water with the epoxy? I don't know? I do have a center overflow and had 2 1 1/2" bulkheads with 2 1" returns. Maybe it was to many holes in such a small space on the bottom? Could have been enough to weaken the glass, then the epoxy reaction.

I will never know what causes the problem just guessing.

I hope yours works out.

 

[RonSF]

Epoxy creates heat when it cures. The more volume of epoxy curing, the more heat. If you mix a gallon in a bucket and never spread it out it can get hot enough to burn you. It is possible that the epoxy was thick enough that it created enough heat to pre-stress the bottom of your tank. The cracking sounds may have been stress related as you filled the tank from a pre-existing crack in the bottom of the tank created before the tank was filled.

I'm still going to go with this route on my new 170, but my plan is to pour the epoxy over a thin sculpted layer of high density urethane foam. I'm hoping that the foam and the fact that I have a tempered bottom will let me sleep at night before I get mine filled the first time. Mine has been shipped three times and arrived three times with damaged eurobracing, so I must fess up to a little apprehension.

I'm sorry to hear about your misfortune, hdtvguy, but appreciate the warning.

 

[RonSF]

Sorry, d-double post.

 

[musicsmaker]

So I now have a 240g tank that is garbage

Could be used as a reptile tank. Just a thought.

It is a all glass tank with foam under the stand.

Two questions:

1 ~ Do you mean a piece of foam between the tank and stand?

2 ~ Does the tank have molding around the top and bottom?

 

[hdtvguy]

Could be used as a reptile tank. Just a thought.

Two questions:

1 ~ Do you mean a piece of foam between the tank and stand?

2 ~ Does the tank have molding around the top and bottom?

Yes I had a 1" foam on the top of the stand that the glass bottom rested on.

No moldings it was a all glass tank.

 

[ravenmore]

man that sux - sorry to hear that dude.

 

[ravenmore]

man that sux - sorry to hear that dude.

 

[musicsmaker]

PS ~ I too think that sux.

 

[spamin76]

Wow - how much epoxy did you use?? How deep of a sandbad did you make?

 

[Thales]

Arg! Thats horrible.

I think I am going to cast mine in three sections.

 

[Carl_in_Florida]

hdtvguy - I just saw your sig... 300 WOOHOO!

 

[hdtvguy]

Wow - how much epoxy did you use?? How deep of a sandbad did you make?

I used 1 1/2 gallons epoxy. I would say the sand was under 1/4"


New tank will have 3/4" low Iron glass (Opti- white)

 

[shred5]

Well all I can say let this be a warning to anyone thinking of doing this.


I did this on my 240g a few days ago let the epoxy and sand mix dry the required time 4 days. I vacuumed all the left over sand out of the tank.

I filled the tank with around 80 gallons of tap water to get the dust out.

I started to hear loud cracks coming from the tank for over an hour. I thought it was just the epoxy from the cold tap water.

Well about an hour later I look over the tank and see water leaking off the stand.


Well the whole bottom glass cracked from the epoxy sand mix:mad2:

I think if you are going to do this use something on the bottom of the glass so the epoxy does not crack and take the glass with it.


So I now have a 240g tank that is garbage

I was able to get the water out quick with a big 6.5Hp 18g Shop Vac so I had no water damage to my floor in my living room.

I hope my home insurance will cover the tank. I did have insurance on it.

Let this be a warning to anyone thinking of doing this. I posted this so hopefully no one else has this happened.

WOW Sorry to hear that.. You can get a new peice of glass cut and installed on the bottom... Might be more work than what it is worth though...

Dave

 

[hdtvguy]

WOW Sorry to hear that.. You can get a new peice of glass cut and installed on the bottom... Might be more work than what it is worth though...

Dave

Thanks,

I don't think it would be worth the time. That epoxy sand mix is rock solid. Getting it off the sides, front back etc. It would be to time consuming.

 

[shred5]

Thanks,

I don't think it would be worth the time. That epoxy sand mix is rock solid. Getting it off the sides, front back etc. It would be to time consuming.

Didnt think about that.. What do you think caused it... do you thing the epoxy could not handle the weight and cracked taking the glass with it... Glass can bow a little, maybe the epoxy can not....

Dave

 

[RonSF]

Didnt think about that.. What do you think caused it... do you thing the epoxy could not handle the weight and cracked taking the glass with it... Glass can bow a little, maybe the epoxy can not....

It is definately not the brittleness of the epoxy that caused it. Epoxy is extremely flexible and it never snaps like polyester resin can. My bet is still on heat induced stress from the curing process if indeed it was caused by the faux sandbed itself.

Rich-
If it was caused by heat, you might actually be making matters worse by heating one portion of the glass independently of another. I would think that the solution would be to do it in thinner layers so that the heat would be more dissipated, but evenly distributed across the surface of the glass.

 

[Brad524]

Thanks,

I don't think it would be worth the time. That epoxy sand mix is rock solid. Getting it off the sides, front back etc. It would be to time consuming.

unless you sanded the edges it may be easier than you think .
the epoxy may bond with smooth glass but it doesn't do it very well. I wouldn't be suprised if huge pieces came off easily

the silicone would come off with it though
so maybe your right

maybe Randy could illaborate on the cause of this ( crack )

 

[spamin76]

I would think that tempered glass would be pretty resillient to the heat change caused by the epoxy... Is it possible that the tank already had a defect or something?