Plywood Tanks
 

Hello Canreefers,

Just curiuos if any one onboard has a plywood tank? If local I'd like to see if not could you post a few pics. Plus general thoughts and experiences appreciated.

Thanks

Jamie

Randy ( ranz ) on this board build himself a beautiful plywood tank. If I remember correctly it is about 300 or so gallons and has glass on 2 sides. I think he has a link to pictures of it in his profile.

Hey Jamie ... no pics for ya but I built a 300G 1" thick MDF tank lined inside and out with fiberglass ... dimensions 96Lx24Dx34H ... 31" waterline and 5/8" glass for viewing area ... 5" brace around the top and 2x2" bulkheads with overflow ... 2x closed loops at back ... all built " in-wall " in my basement with a 70G sump underneath and " soon to be installed " ( thanks Tony :) )
55G refugium as well ... if you plan it correctly then it is easy to do ... a 3" wide trim around the front to help support the front glass ( 45 degree bevelled edge ... look like a picture frame ) ... 3" screws every 2 " for all wood joints along with construction grade glue ... 3" x 1/2" center brace

If I had it all to do over again ( and I might :smile: ) ... I would build it 96Lx48Dx34H ( 31" H waterline ) ... 2 overflows ( 1 on each side with 2" bulkheads on each ... that way it would only have to " skim " 4 ' each into each overflow )

If you have any questions on the construction just let me know

Cheers

Dale, Thanks. Just stopped by his site. Hope he stops by and reads this thread. I like the double thickness for the plywood idea. wondering if he has center braces or trim at all?

Rasta, Sounds good thanks for joining in. Do you have a rough cost on your project? Also was it a big PITA or not bad? The 3"x 1/2" center brace are you meaning 1/2" thick ply? How many coats of resin? Whats your thoughts on plywood vs glass tanks? Any pro or cons you would like to mention?

I think it was about 40 a sheet for the 1" MDF ( 3/4" marine plywood would work just fine ) ... the 3" x 1/2" brace is made of glass ( oops ... hehehe ... I did glass here because I did not want a " shadow " in the middle of the tank ) ... the whole project was not too bad as long as DIY is your bag :smile: ... depending on what product you use for the coats I would recommend using West Systems epoxy ... it costs a bit more than the rest but you will be very happy with the results ... I actually built a arogrocrete wall around the exterior ( approx 3/4" thick with eggcrate as the base ) of the tank for extra filtration and also to protect the tank from the live rock accidentally scratching the surface

As to pros and cons ... the wood tanks are great insulators and cost way less than the glass counterparts ... you could get a starphire viewing glass which I would have done had I known about it at the time ... drilling can be done with simple hole saws for alot less than glass ... I guess I cant really think of a con and if I were to do it again I would just go bigger and plan ahead for circulation a bit more ( I had to drain part way to install closed loops )

Cheers

Rasta, Thanks again, I appreciate you taking the time to help answer the questions. As I'm sure you have figured out I'm thinking of biulding one myself. You don't have say a rough total project cost do you? Also how long has the tank been up and running?

Depends on how big you go for cost ( mine was built 5 yrs ago so prices have gone up since then for wood and have not looked at the epoxy in that time either ) ... I think mine cost about 600 beans at the time I built it including stand and almost half of that was the front glass ( call local glass manufacturers as some will sell direct to you )

I took it offline for almost a year and a half and moved everything into the sump and the 50G ( live rock caused a leak in back panel so that is when I decided to make a arogrocrete wall around the perimeter ) ...

If you are serious about building one Jamie then the 3 most expensive components are ... 1) the front glass 2) West Systems epoxy ( the best IMO ) 3) the plywood

A few phone calls will give you a good idea what your project will cost today ... my only advice is the epoxy is no place to skimp and after hours of research I found West Systems to be the best ( local boat store should carry it )

Cheers

Is there any set rule as to the minimum trim required around the front. If you wanted a viewing pane of 24" you would have to make the tank 31-32 inches tall to hide the frame if it was in-wall.

Jamie, I have been looking at this also but I have pretty much concluded it would be hard to make it look nice if it was a free standing tank(by this I mean it would not look as good as a glass tank with out a lot of work) .
If it was built into a wall it would be the way to go though, unfortunatly the new house I bought does not lend its self favorably to a "In wall" tank.

Steve

I would leave at least 4" of frame at the bottom for a DSB. That way you would only see the top of the DSB and not the grungy stuff lower down.

That is all you see on the front of mine Kim ... sloping higher to the back

Cheers

Just curious Steve ? ... by not looking nice as a free standing what do you mean ? ... are you talking about viewable side panels ?

Cheers

well in order for me to have it as wide as I like I need to be able to acess it from both sides so basicly I would be using it as a room devider so I would have to get glass for two sides and one end. as it would look funny with one side just wood. by getting a glass tank you don't have that problem.. just that..

I think a plywood and glass tank lends it self to a "In wall" or "corner" type install better than a 3 side.

Now that I have said that I think I have a way to do it LOL but that would involve columes and such.. hmmm I think I have a idea..

If I used large columes 4X4 or 6X6 to finnish the edges I could carry them on to the roof. this would provide all the stability you need for your wall corners and allow you to go with 2" of framing around the glass.

Has anyone gotten a price on 5/8th or 3/4 thick glass?

I think that building a "free standing" ply and glass might be more expensive in the long run, But it might be more apealing if done right.

Steve

Its all your fault Rasta, just when I had convinced myself to buy a tank you got me going on this again :mrgreen:

questions for ya.

1, is there anyway you could get some one with a camera over to take some pics?

2, I am interewsted in how you did your joints you mentioned 3" screws is that into the end of the particle board? and did you use any other external bracing?

3, how big is your viewing glass and how thick?

I had planned on using two layers of 3/4" plywood if I did this. I don't feel the extra cost of marine grade is warented but I will look into that also.

4, Why did you decide to use fiberglass? (just picking your brain here)

5, what is your feeling on 45 degree joints? I was thinking of making the tank bulge at one end like a bay window.

Any other info you have either by links or in your head would be greatly apreaceated.

Steve

Isn't MDF horrible after it gets wet?

Aslo, is this economical for smaller tanks? Say 70-120 gal. You could sure drill the heck out of it for closed loops which is a nice benifit.

Whats the difficulty on something like this?

The whole idea of fibreglass is to waterproof it so it does not get wet :lol:

Does not matter what you decide to use for the main structure whether it be Plywood ( if plywood gets wet it will split as well ) or MDF as long as it can handle the water pressure.

You could use this for any size tank but the bigger the better :eek:

Cheers

Guilty as charged :cool:

1) I only have pics of the completed tank as I did not think to document the construction when I built it

2) I basically used the 3" screws and also a construction grade wood glue ... also a 5" perimeter brace around the top ( If I was to do that again I would simply do (3) x 5"x1/2" glass cross braces in the middle and 2 on the ends instead so that I get more light into the tank ... very small shadow at very top )

3) I used 5/8" glass and the viewing area is 90"x29"

as far as plywood goes 2x3/4" would be VERY sturdy :)

4) as far as fibreglass goes it was the most economical way to seal the wood and provide a more rigid perimeter ... looked at all kinds of different sealers but came back to fibreglass every time.

5) as far as 45 degree joints I did not have the skill to do that so I just reeinforced with screws / glue / fibreglass ( probably overkill ) but I know it is strong )

not sure on the pressure dynamics that a bay would cause so cant comment there ... would be cool though


If I think of anything else I will let you know


Cheers

isn't this the job of the two part epoxy? , to seal the tank, this was my understanding from other plywood and glass tanks.

Steve

StirCrazy Wrote:
Without proper bracing you would probably get the bow anyway. :mrgreen:

Trig-no-metric is on his last chance with glass going into five years......I think all four sides plywood would be his next home...... :razz: :lol:

ok, I am missin something who is Trig-no-metric ?

Steve

He's the trigger!!!

The 2 part epoxy goes over the fibreglass matting ( or not ) ... it is up to you really ... by putting the fibreglass matting down you get a stronger finish ( you dont have to use the matting ... you can just put the epoxy right on the plywood too )

Cheers