jt48's 240 Build Thread

[jt48]

I can edit my own thread right? Because I really don't know what I'm doing.
The beginning here will be sort of a trial run.

I had been saving up for a MarineLand Deep Dimension Starphire front 250 or 300 for a while but came across a used never seen water 240 gallon acrylic tank for sale here on ReefCentral. Tank measurements are 72x24x32. I acted quick and hundreds of miles later it was mine. Saved well over One Grand.

Here is the pic...

 

[jt48]

Thanks to all of you, I learned that without a doubt, that acrylic tanks need to be placed on a flat surface, not just the outside rim. So here I had a 72x24 tank that fit your standard stand for a 180 gallon. However, those stands are open topped and would not suffice. The Oceanic stand for a 215 is flat topped but did not have a trim. I did not like the Oceanic stand look IF a trim was then added. I contacted a local contractor. I specified that I needed a flat top with upper and lower supports and I wanted a trim. Price range was $1100 to $1300.
I got a 2nd and a 3rd price qoute. Everyone was in the same price range. I did not feel comfortable building my own from scratch so....I purchased a Perfecto Pine Majesty stand for $300

 

[jt48]

Here is a pic of the bottom of the Perfecto Pine Majesty stand. No cross brace supports to prevent sagging from large sumps!

 

[jt48]

I purchased one 2x2x8, one 2x4x8 from lowes:

 

[jt48]

Braces:

 

[jt48]

The 3/4" plywood was kinda warped so I upgraded to a solid piece of Aspen:

 

[jt48]

1/2 inch thick Polyshield to be placed in between board and tank:

 

[jt48]

Bottom braces installed:
<a href="http://s1012.photobucket.com/albums/af250/osprey48/jt48s%20240%20Build%20Thread/?action=view&current=jt48s240BuildThread016.jpg" target="_blank"><img src="http://i1012.photobucket.com/albums/af250/osprey48/jt48s%20240%20Build%20Thread/jt48s240BuildThread016.jpg" border="0" alt="Photobucket"></a>

Top Braces installed and interior painted:

Couldnt locate Marine Paint so I used:

 

[jt48]

Solid Aspen in place:

And 1/2 Polyshield:

Close up of stand, then 3/4 inch board, then 1/2 inch Polyshield, then tank:

 

[jt48]

Bought two 8 foot pieces trim and spray painted black:

 

[jt48]

Tank in place! The tank sits in front of two windows that face northwest shaded from the sun by trees and neighbors. I have full access to the rear of the tank from outside.

 

[mprygh]

Hard to say by looking, but looks like it may fail.
You have to support 2000 pounds of water, and who knows what lighting, rocks, etc.
Plus, you will probably lean on it.
All of the load will be on those 4 cross braces, which are just held with the little
brackets with the tiny screws. Given extra loads, uneven loading, that could be 700 pounds per brace.
Get 3 friends, and jump on it.
All cross braces really need to be supported directly, with a 2x4 to the floor, on each end. Which yes, may cause issues with the door.

 

[mprygh]

To clarify test:, get 3 friends (4 people), and jump on a single cross brace.
You would need 15 people to equal the weight of the whole thing.

 

[jt48]

Thanks for the input. With the following info, do you still believe it would fail?

The board and the tank does not just rest on the braces. The board and the braces are not designed to hold up the tank. They are designed to provide support to the acrylic to prevent bowing/sagging. The board and the tank rests on the stand itself.

 

[mprygh]

Hmm, that definitely changes the forces on things.
Thoughts.
1) Did you screw the cross braces to the top board?
If you did, then the cross braces really do act as stiffeners for the top board,
distributing weight out to the sides.
If not, the "bowing" of the tank will still put huge pressure on those brackets.
Much less, since it is shared with the top board though.
2) Is the outside edge of that top board really strong.
You have a huge amount of weight on the edge of the cabinet.
A board like that is simply strips of wood glued together. Not real plywood.
So all that weight goes into shear force on the glue joints on the outer strips.

I really do not know the answer. May hold. May not.
And over time, not sure what the moisture/humidity would do to the glue.

I would definitely suggest adding some support structure inside to hold up the ends of
those cross braces. But plan it, or you will not have room for a sump.

 

[Ward1]

It's so much easier to strengthen now than it will be later. Lumber is cheap compared to the potential problems here. I think saltwater is about 8lbs a gallon? My 300 hundred sits on several 6x6 legs with about 12 2x8's screwed together on top of the legs.

 

[mlb75]

looking good, while I wouldn't be nearly as worried as mprygh my only comment is the cross braces will be holding some of the load so it might not hurt to support them with say a 1x4 from the bottom to the underside of the brace at least in the back. If nothing else make sure you have 2.5" or so screws going from the outside of the stand into the ends of the braces. You're more than likely perfectly fine already since with the 3/4 sheet on top of them it will be distributed quite a bit but like just about everyone here I like to overbuild things as well. With that tank you can't over support it.

Next thought is what are you doing for a sump and how are you getting it into the stand? If its a decent size you're more than likely going to have to remove some of the front or back supports. If you do that I'd recommend going in through the back and then adding wider supports.

For those of us equipment junkies what else are you planing to run for skimmer, return, other flow, lights, etc...

 

[mlb75]

there are many threads here that go into the math of how much most of us overbuild our stands. It can never hurt piece of mind to overbuild but 12 2.8's WOW you could probably set your whole house on that. To give you better piece of mind call some of the major acrylic tank builders and talk to them...

 

[Ward1]

there are many threads here that go into the math of how much most of us overbuild our stands. It can never hurt piece of mind to overbuild but 12 2.8's WOW you could probably set your whole house on that. To give you better piece of mind call some of the major acrylic tank builders and talk to them...

Yeah, it is. But you only want to build something like that once. More importantly because it is in a wall where there used to be a closet and access will be an issue once everything in place.:hammer:

 

[jt48]

1) Did you screw the cross braces to the top board?

Umm, the cross braces (2x4's) are screwed to the tank stand. The top of the cross braces lay flush with the top of the stand. The aspen board lays on top of the stand and the top of the braces evenly. I did not glue or screw the aspen board to the braces or the stand. Reasoning?-Where is it going to go, I'll have 2000 pounds on top of it. This is what I was thinking as supported by the lfs-the stand in by itself without any modification is built to hold that weight. By it being acrylic I only needed to have a flat bottom to prevent sagging.

2) Is the outside edge of that top board really strong.
You have a huge amount of weight on the edge of the cabinet.
A board like that is simply strips of wood glued together. Not real plywood.
So all that weight goes into shear force on the glue joints on the outer strips.

Umm, IMO this solid aspen board was much stronger than plywood