2000 gal plywood sump

[on the spot]

closed poly tanks for some of that volume...

Cost. The tanks would cost ~ $2000...

maybe. IBC's with new poly tanks are $200 for 275 gallon capacity. rinsed sugar tanks about $80 or so there around Dallas.

but you have a big door? drawn on the greenhouse - 1500 gallon tanks are $600 bucks.

right not the thing to look at, but still an economical option.

regardless of how it goes, it is fun to watch.

GL moving forward.

 

[der_wille_zur_macht]

My 360g wood tank had a double layer of 3/4 plywood eurobrace about 4" wide. I measured for deflection and there was literally zero. I would have been happy with "some."

 

[karimwassef]

There's a garage door in that back section of the sunroom. But the 1500 gal tank costs $900 and the small one is $600 (before shipping)... so ~$2000 shipped

http://www.reefcentral.com/forums/showpost.php?p=25214341&postcount=622

IBCs are commodity and used ones sell for peanuts but I can't make a giant open sump with them.

 

[karimwassef]

Which is stiffer over a 13' span:

1" square stainless tube?
4" x 1.5" plywood eurobrace (1.5" ~ 2 x 3/4" overlapping joints)

I think it's the plywood but by how much?

 

[on the spot]

...I can't make a giant open sump with them.

There, that part about the giant and the open.

What's it for?

I've seen most of your threads on the build but must have missed that post on the why you want so much open capacity in the sumps.

That's also why I said 600 for the 1500 gallons tank. I was thinking the giant closed water tanks, not the open trough.

any way it comes together I'm still fascinated.

Best of luck.

 

[karimwassef]

Ah... my tank has multiple systems that can surge/flood. My experience is that the sump needs to be large enough to accommodate a complete tank drain with these kinds of systems. The reality is that this is an acquired rule of thumb, not an absolute measure.

Second, I need a very slow flow with the widest possible cross-section to allow the water to fully clear of bubbles. The configuration is such that the "travel" is 8' and the width of the tank is 13'. That means that the water in the sump is moving at 1/3 the highest flow in the DT at 3x the width.

This might seem excessive but this "reciprocal rule of thumb" allows me to do just about anything I want with the water flow and still have a reasonably clear tank.

Sump (1300gal) ~ DT (1600gal) in volume
Sump W (13') ~ DT L (12')
Sump L (8') ~ DT W (8')

I'm also using a large settling filter to extract particulates for re-injection as food...

So you're thinking ...??!?!

These mechanisms don't change the bubbles and particulates in my system. They allow me to control when and where they appear in my DT without compromising two key variables: food (~particulates) and flow (~bubbles).

 

[Mebeknob]

So if I were you I'd reshape your tanks with the max length being 8' simply because that's the length of plywood. Then you don't have to worry about joints besides those at the corners.

With the way you have it 3/4" plywood with a plywood eurobrace will Work with caution.

What epoxy are you planning on using?


Sent from my iPhone using Tapatalk

 

[karimwassef]

I've used US Composites 635 for years... great stuff

http://www.uscomposites.com/epoxy.html

15 gallons is ~ $600

The tank is 8' long... but 13' wide.

 

[karimwassef]

also, my DT is 8' x 12' with a plywood floor.

But that's made with 4 layers = 3" thick of overlapping plywood seams. check out the video that walks through the build.

I've done this kind of thing on a smaller scale before:

http://www.reefcentral.com/forums/showthread.php?p=21034142&highlight=plywood+sump#post21034142

I've built a cube 24x24x24 and a plywood sump 72x24x24

<a href="http://s1062.photobucket.com/user/karimwassef/media/B8AD5D28-F9DA-468A-9997-E7AF5A1DFFED-459-0000010A620D5D13_zps7bfa3a3e.jpg.html" target="_blank"><img src="http://i1062.photobucket.com/albums/t496/karimwassef/B8AD5D28-F9DA-468A-9997-E7AF5A1DFFED-459-0000010A620D5D13_zps7bfa3a3e.jpg" border="0" alt=" photo B8AD5D28-F9DA-468A-9997-E7AF5A1DFFED-459-0000010A620D5D13_zps7bfa3a3e.jpg"/></a>

<a href="http://s1062.photobucket.com/user/karimwassef/media/9C625286-C48F-43AC-B65C-FA5A90F728C0-368-0000004F13C5C315_zpsf471b615.jpg.html" target="_blank"><img src="http://i1062.photobucket.com/albums/t496/karimwassef/9C625286-C48F-43AC-B65C-FA5A90F728C0-368-0000004F13C5C315_zpsf471b615.jpg" border="0" alt=" photo 9C625286-C48F-43AC-B65C-FA5A90F728C0-368-0000004F13C5C315_zpsf471b615.jpg"/></a>

<a href="http://s1062.photobucket.com/user/karimwassef/media/C5D2F8D6-03FC-49ED-BF7E-B77A5098C188-368-0000004F167AE608_zps90117f29.jpg.html" target="_blank"><img src="http://i1062.photobucket.com/albums/t496/karimwassef/C5D2F8D6-03FC-49ED-BF7E-B77A5098C188-368-0000004F167AE608_zps90117f29.jpg" border="0" alt=" photo C5D2F8D6-03FC-49ED-BF7E-B77A5098C188-368-0000004F167AE608_zps90117f29.jpg"/></a>

<a href="http://s1062.photobucket.com/user/karimwassef/media/84E5ED47-EDCF-4D36-B6DE-785D2DCC6E66-368-0000004F1715552A_zps3851b666.jpg.html" target="_blank"><img src="http://i1062.photobucket.com/albums/t496/karimwassef/84E5ED47-EDCF-4D36-B6DE-785D2DCC6E66-368-0000004F1715552A_zps3851b666.jpg" border="0" alt=" photo 84E5ED47-EDCF-4D36-B6DE-785D2DCC6E66-368-0000004F1715552A_zps3851b666.jpg"/></a>

<a href="http://s1062.photobucket.com/user/karimwassef/media/2171D2D5-F3D5-48BB-921D-FCD8676795EC-1910-000001EF856F664C_zps6a96e1b0.jpg.html" target="_blank"><img src="http://i1062.photobucket.com/albums/t496/karimwassef/2171D2D5-F3D5-48BB-921D-FCD8676795EC-1910-000001EF856F664C_zps6a96e1b0.jpg" border="0" alt=" photo 2171D2D5-F3D5-48BB-921D-FCD8676795EC-1910-000001EF856F664C_zps6a96e1b0.jpg"/></a>

<a href="http://s1062.photobucket.com/user/karimwassef/media/692196E5-31BB-46BC-90E9-181CA4C2D516-459-0000010A6C03A541_zps55759039.jpg.html" target="_blank"><img src="http://i1062.photobucket.com/albums/t496/karimwassef/692196E5-31BB-46BC-90E9-181CA4C2D516-459-0000010A6C03A541_zps55759039.jpg" border="0" alt=" photo 692196E5-31BB-46BC-90E9-181CA4C2D516-459-0000010A6C03A541_zps55759039.jpg"/></a>

<a href="http://s1062.photobucket.com/user/karimwassef/media/74F55BFA-BD45-4B86-85A1-8250FB608DF9-459-0000010A7739F56E_zpsccf96593.jpg.html" target="_blank"><img src="http://i1062.photobucket.com/albums/t496/karimwassef/74F55BFA-BD45-4B86-85A1-8250FB608DF9-459-0000010A7739F56E_zpsccf96593.jpg" border="0" alt=" photo 74F55BFA-BD45-4B86-85A1-8250FB608DF9-459-0000010A7739F56E_zpsccf96593.jpg"/></a>

<a href="http://s1062.photobucket.com/user/karimwassef/media/0367B40B-36E5-472C-9884-C8BED7E0C3B3-459-0000010A599F95F6_zps391bbfef.jpg.html" target="_blank"><img src="http://i1062.photobucket.com/albums/t496/karimwassef/0367B40B-36E5-472C-9884-C8BED7E0C3B3-459-0000010A599F95F6_zps391bbfef.jpg" border="0" alt=" photo 0367B40B-36E5-472C-9884-C8BED7E0C3B3-459-0000010A599F95F6_zps391bbfef.jpg"/></a>

 

[Mebeknob]

From an engineering standpoint, whatever you did that works for a 24" depth tank will Work for the 18" depth tank in theory regardless of length and width


Sent from my iPhone using Tapatalk

 

[karimwassef]

Ok... so wild idea...

What if I used the concrete slab floor and plywood sides?

The floor will already have epoxy on it.

I would use epoxy to glue the sides. The rest stays the same.

The wood to wood butt joint would be replaced with an epoxy (on wood) to epoxy (on slab) joint.

Once the two are attached, I would apply an epoxy filet and a couple more layers over that.

The plywood bottom wasn't really doing anything. It would save ~ $300 in wood and about $100 in epoxy given that I was planning on costing the bottom floor side of the bottom plywood to be fully sealed.

I am giving up flexibility in redesign, but I can probably redesign around that sump:

Also, I am expecting to have to walk into the sump to access the far wall... and even using a fiberglass ladder in it to access the raised fuge... concrete + epoxy directly should be more durable?

 

[Mebeknob]

Makes sense to me. With that route I'd consider doing block walls so you can sit, step or put stuff on them.

https://m.youtube.com/watch?v=IjikcTxMiak

The only issue I see with this would be cracks. If cracks develop in the concrete floor it will go through to the foundation. Honestly not really a problem, more of something to be aware of.


Sent from my iPhone using Tapatalk

 

[karimwassef]

The wood has more continuous support and should be cheaper.

I've vacillated between concrete block, rebar and concrete, and wood...

Block is heavy and has weaknesses in the joints.
Rebar wall would be very messy and a lot of work.
Wood should be cheap, light and relatively easy.

 

[karimwassef]

The floor is 18" triple rebar construction... that's why it's so expensive.

With drylok and epoxy, it should be near impregnable?

 

[45commando]

I've vacillated between concrete block, rebar and concrete, and wood...
.

Re-bar & concrete got my attention. Have you priced making the entire sump walls with poured concrete & re-bar supports? The re-bar can be epox'd into the existing slab as upright supports & re-wire used to add lateral . You can build the form & pour the concrete in small stages, so you're not purchasing a bunch of plywood for forms, to then be trashed after a single pour. You are also not limited by the lumber dimensions & won't have to employ structural walls as added security. Just wanted to give you another avenue. Best of luck with your build

 

[karimwassef]

Actually, that's why I went to plywood. If I'm using the wood forms to pour concrete, I can just leave the wood and coat it in epoxy. It's just less work to get the desired result.

I could make smaller pours but concrete already takes a long time to cure and building it continuously should provide the greatest strength, I believe. It's also a lot of perimeter to pour in small sections.

I was never a big fan of wood really. But I have to admit that its strength to weight ratio does make it a very convenient building material. It won't stop a truck - concrete will. But for 99% of the time, it's a lower cost, lighter weight, strong and convenient building material.

Its weakness is its longevity. While rebar and concrete could last 100 years (more), wood would eventually rot, mold, flake, burn, dry, be eaten ... or otherwise disintegrate. Epoxy changes the math though. Fully epoxy encapsulated plywood has the best of both worlds.

It could survive a flood, hurricane- not sure about tornados, earthquakes and fire though

 

[45commando]

I could make smaller pours but concrete already takes a long time to cure and building it continuously should provide the greatest strength, I believe.

I understand your choice for all the reasons you stated, but just wondered if you had crunched the numbers. The form could be constructed with 1/4" ply or even hardboard sheet, so long as it is braced.

Concrete can be poured in stages with no loss in strength. The strength comes from the type of concrete & how dry the pour is (drier is stronger)

If you build with ply, have you considered constructing a center brace/ cross braces ( really a tie or ties) to help prevent the side walls bowing out ? A length of small angle iron, a 2x2 or even some PVC pipe would work. HTH

 

[karimwassef]

I have considered both kinds of bracing actually (see above), but I really need an open space.

I am planning on a 1" square stainless steel tube around the outside perimeter. While it is possible to deflect a 13' stretch of 1" square tubing, I don't believe the force exerted by 20" of water would be sufficient.

On one side!!!
The support is 3/4" plywood + 2x12 beams + 1" square ss + 1/4" epoxy

And in the other corner!!!
Pressure of 20" of water applied over 13' span



Would a eurobrace top make it even more solid? Absolutely! Do I need it? I don't think so.

I can always brace is once I fill it and measure actual deflection...

 

[karimwassef]

Confession: working with concrete is also much dirtier and might require renting equipment. I also gravitate towards my comfort zone, especially if the cost differential is low.

Have I calculated the full cost including material and time? No
Have I "rule of thumbed it" and considered that the benefits of the alternate way will likely be less than $100 - yup

 

[45commando]

Very good point: work with what you are more comfortable with. Best of luck & I'll be waiting to see the finished project.