Rocks in a Tank Experiment!

[f1oored]

I've been on this forum for several months now and during that time many people have asked about the number of rocks they can safely put in their aquariums. This is of course a valid question because no one wants their tank to crack and empty x number of gallons onto their floor.

To safeguard against these cracks many people use an eggcrate type layer on the bottom of the tank to distribute the weight evenly. It's a nice thought but is it really necessary?

In my experiment I am going to pile rocks into a 10 gallon aquarium on the bare glass. Stacking all the rocks on one small rock in the center of the tank. How many pounds do you think the tank will hold? Mind you we are talking about bare glass with only a few inches of water covering the bottom.

I will take video and share it once it is ready in the video forum. I will also post the results in this thread.

I would love to hear some guesses on the breaking point. It will be like a game and whoever is the closest will win 25,000 points.

I will post the results at 4:00PM Forum time tomorrow.

[Chrona]

What do we win? The tank? lol

In any case, fish tanks are made with tempered glass right?

Btw, if you are doing this in the name of science, you would put the whole thing in your tub and fill it with water. A full tank would drastically reduce the apparent weight of the rocks due to bouyant force, and so would, in essence, reduce the load on that one spot while evenly adding more to the rest of the area. If you only have a few inches of water at the bottom, I have no doubt a stack of rocks will crack even tempered glass. Full of water though......dunno.

[f1oored]

So how many pounds would you guess Chrona? With the experiment as described with only inches of water.

[Chrona]

I'll get back to you in a sec after I find out whether 10 gallon fish tanks are made of tempered glass or not lol.

[cocoa_pleco]

with only a few inches of water- 50lbs

[f1oored]

50 lbs huh? That sounds like a lot of rocks for a 10 gallon tank.

[f1oored]

Yes 10 gallons are made of tempered glass (as are all glass aquariums to my knowledge).

[Chrona]

And how big is the rock you are stacking all of the other rocks on?

(Sorry, I'm an engineering student)

[f1oored]

About softball size but not flat so it may only have a few points of contact.

[f1oored]

Like a softball but not flat???? Did I actually write that?

[*Sarah*]

Like a softball but not flat???? Did I actually write that?
Well, it appears so:11:

[Chrona]

I'd say about 30 lbs then. It really depends on the surface area of the contact points, especially on glass.

[f1oored]

Sarahmom... your guess?

[Chrona]

I say everyone who takes a guess has to donate 100 pts to the closest guesser at the end :)

[*Sarah*]

Sarahmom... your guess?

Hmm, I'm really not good with stuff like this at all, and I really have NO clue, but let's say...80lbs?? I'm putting a lot of faith in that tank :thumb:

[f1oored]

Alright closest guess gets 25,000 points.

[Gelo_USA]

Hmm, I'm really not good with stuff like this at all, and I really have NO clue, but let's say...80lbs?? I'm putting a lot of faith in that tank :thumb:

WOW ur really putttinggg ALOTTTTTTTTTTTTT of faith lol

but take into consideration tht a 10 gallon will be way more resistant than any bigger tank the bottom glass being smaller it can hold way more weight than a bigger tank would

40lbs will do it

[cocoa_pleco]

im staying with my 50lbs.
GOD,I NEED POINTS

[sergo]

55 lbs if you can stack it in there.
floored, you like doing experiments don't you.
now is this a cheap tank with the thinnest possible glass or a quality one with a little a little thicker glass?

[KneeKickLou]

im going to say 43lbs 13oz.

[Lady Hobbs]

Seeing this 3 month old thread brought back to life offered me a chance to ask you something I wanted to ask you previously.

Why did you use such huge rocks? Your's look like they come from Mt Rushmore. LOL Rocks that size would really scare me without the egg crack under them.

[f1oored]

I like the look of big rocks.

This tank is the cheapest of cheap 10 gallon tanks. There is nothing special about it. The experiment is done and the video is ready. 9 more minutes to get your guesses in.

[f1oored]

The video is up.

[f1oored]

All of this is in the video so if you don't believe me just watch it.

I placed 91.8 lbs of rocks balanced on one single rock on a bare bottom tank and it didn't crack. I then removed all but a few of the rocks and stood on the rocks remaining in the tank. The total weight was over 220 lbs. The tank still did not break or crack.

The glass on my big tank is 4x as thick as the glass on the 10 gallon. I have about 200 lbs of rocks but they are spread out and on a gravel substrate. If the 10 gallon can hold 220 lbs on one rock then my tank isn't even coming close to it's limit. I hope that answers your question Hobbs.

The egg crate suggestion is based on a myth. Your tank isn't going to crack unless you put an unholy ammount of rockwork in it or drop a large rock into it. I doubt this will put the argument to rest because people will choose to believe what they want regardless of facts and evidence. But I should get some points for trying right:)

[cocoa_pleco]

WOW, holy sh*t those tanks can hold alot!
I thought my 50lb guess was high

[*Sarah*]

But I should get some points for trying right:)

Well, I didn't give u points, but I gave you an ice cream cone :)

[f1oored]

Ice cream is way better than points!

[Chrona]

WOW, there goes my guess. I might as well quit engineering now huh? LOL