love my wavebox. 3 years in my 90gal, almost 2 in my 180 :biggrin:

I'm plugging my ears and doing the "lalala" thing about the reduction in tank life though. My used tank has an unknown number of years on it and I shudder at the thought of having to take it down in the next 5 or so years (although the 15-20 years tank life talk was encouraging, I thought it was much less).

If it helps I can assure you silicone is not effected by mechanical cyclic loading so it's immune to fatigue type failures in most cases such as aquariums. The only fatigue issues with silicone are related more to electronics which have thermal cyclic loading. In addition even if fatigue failure was possible the amplitude from the cyclic loading is actually very small, the pressure from the wave is only fluctuating a few inches in comparison to the total pressure of 20+ or so, so it's not even close to something that would raise fatigue concerns anyway. Fatigue issues relate more from reverse cyclic loading where the load reverses direction created an a total amplitude greater than the actual static load (similar to why bolts are always preloaded).

The simple fact is fatigue failure is completely impossible from a wave box and it's a bunch of BS and like most stuff on the web is just spread by a bunch of people who know very little about the subject.

OK. I can breathe now.

There you go Brad stop you whining and get that wave box going :mrgreen: oh ya we need pictures of that thingy too. and try it with out the box i did for a bit with mine in the 150 and it worked pretty good. Its like a fat MP40:razz:

Including Tunze apparently! Maybe their warning is more to do with liabilities and a 'just in case' ?

I would imagine they're covering all their bases.

Yeap it's just politics

still could cause the stand to fatigue and fail:wink:

I think this would be the biggest contributor. Either failure, or shifting. My stand is pretty solid, so I think I'm good.

No, we can't breathe yet if you read what fishytime just had said.

Just breathe very softly. Borderjumper's tank, IMO, broke from the wavemaker causing shifting in the tank and/or stand. The bottom split out corner to corner. Messy ****e.....

I appreciate the fact that you are educated (engineer I think?).....but could you explain it in terms that the AVERAGE person can understand.......I mean I just cant see how 2000lbs of water shifting back and forth in a glass box doesnt fatigue the tank in any way????......school me please:mrgreen:

Gooosh ... :cry: I should not have read your thread

Well even the cheapo silicone I used on an ATO before was rated at something like 190psi of strength so if you take that surface area across the whole tank you can see how its strength exceeds the weight of the tank contents. Like it was stated a little earlier the weakness would likely come from the tank being on a cheap stand (pressboard, etc.) since your tank's centre of gravity would be prime for folding the stand like a house of cards.

If I understand things correctly (which I might not :) ) .... I think the difference is that it's not the full 2000lbs of water shifting back and forth. The tank is already under load from that 2000lbs, and that in turn is shifting by 1" vertically spread apart the length of the tank (so 4', 6', 8' ... whatever). So the left side probably has to vary from 1900lbs to 2100lbs and the right side from 2100lbs to 1900lbs. If that causes the tank to fail then the tank things were well outside the margin of safety to begin with.

Further, if I understood Steve correctly, the silicone can handle a mechanical shifting load better than it could from going from hot to cold. This makes sense to me on an intuitive level, silicone has some elasticity to it and its adherence to glass (due to the silicone seeping into the pores of the glass itself) is inherently very strong.

A stand that is not properly supporting the weight of the tank is a different matter. And that could cause a tank to fail regardless, wavebox or not.

Here's how I look at it: Do I worry about a tank blowout? Emphatically yes, it scares the bejeebus out of me, like I'm sure it would any hobbyist. Would I worry any less if I took my wavebox out? Not whatsoever. I'd worry all the same.

Good point I agree! I worry more about my wallet than the tank tho!