Ply aquariums
- Thread starter Antj88
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I have a plywood tank 8x4x4.5 that I built. Lots of things to look out for. I based most of mine from a 2200gal plywood build on youtube. His build is also on this site I believe. Stacked 2x4s, log cabin style. Very strong, well insulated tank. I recommend fiberglassing the entire inside, before pond shield epoxy though. Would like to see your plans, it would be easier to give advice.
I've made a bunch, but never more than 24-inches deep. At that depth, a simple screwed/glued box made of 3/4-inch plywood, sealed inside with epoxy (Pond Shield or other...), and with a viewing window cut out of the front and a piece of 1/2-inch glass siliconed in is perfectly adequate. No need to be concerned about interior corner reinforcements, fibreglass/resin, etc. Just take your time and don't take any shortcuts. Don't fall victim to the adage that afflicts so many builders: "Why is there never time to do it right, but always time to do it twice?"
Once you increase the depth you will require exponentially stronger construction and thicker glass. A combination of limited funds and limitless cowardice have prevented me from going that far; I look forward to following your construction and living vicariously through your project.
Good luck, keep us posted!
Once you increase the depth you will require exponentially stronger construction and thicker glass. A combination of limited funds and limitless cowardice have prevented me from going that far; I look forward to following your construction and living vicariously through your project.
Good luck, keep us posted!
I been watching that joey king of diy guy on youtube n gunna pretty much copy his design
I like a lot of King of DIY's stuff, but honestly, his tank design doesn't strike me as the best. He seems to imply that the external bracing on corners, etc. is making it stronger, but I really doubt that's the case. It looks nice, but...Joey is a little hyper, and I wonder how often he actually sets up a long-term tank. Everything is always being torn down, moved, re-vamped, "improved" and often changed just for the sake of change. If you see yourself doing it like that, great; if you want a stable, durable, reliable long-term design I'd look a bit further.
I would suggest spending some time going through the DIY section of MFK and reading through a bunch of the threads there. Plenty of ideas, plenty of alternating viewpoints regarding designs and construction techniques, and...most importantly...plenty of pitfalls and problems discovered by other builders. Some of them find solutions, others simply alert you to the potential existence of issues you might never have thought of, but all well worth reading and considering.
I would suggest spending some time going through the DIY section of MFK and reading through a bunch of the threads there. Plenty of ideas, plenty of alternating viewpoints regarding designs and construction techniques, and...most importantly...plenty of pitfalls and problems discovered by other builders. Some of them find solutions, others simply alert you to the potential existence of issues you might never have thought of, but all well worth reading and considering.
I copied his build for my 280 gal. Great tank. I do not feel that design is even close to sufficient for the size we r talking about. Ur talking about 4.5 tons of water...
Suggestion: Design your tank. Build a small version first so you can get the calcs right and you can visually see the problems. The cost is insignificant compared to doing a large tank the first time and you blow it. Use a high grade 3/4" plywood. Marine grade is not necessary. Build and install a picture frame type brace around the top of the tank about 1" from the top. Then build cross braces across the picture frame. This keeps the top part of the tank from bowing. I recommend pocket framing the glass to add to the structure. Dry build the tank. Do NOT use wood glue or any bonding agents. Stainless screws are unnecessary but good wood screws are. Set your glass dry to make sure it fits. Unbuild the tank. Rebuild the tank by using MAX ACR or Pond shield or whatever epoxy resin you want to and wet drive the screws back in. Use the same epoxy to bond the plywood together. The epoxy should squeeze bead out when the screws are drawn tight. This is why you don't use wood glue. Let the tank sit on a FLAT surface to cure for several days. After the tank has cured it should have a ring to it when you tap it.
Get your materials together to fiberglass and epoxy the OUTSIDE of the tank. Fiber glassing the outside makes for a stronger build. Let it cure for a few days. Mix and color some epoxy for the inside. Thin down the mix with acetone about10%. This will alow the epoxy to draw into the woodgrain. Let it cure (so the acetone can flash off). Sand the gloss off this first layer and roll at least two more epoxy layers on top. Set your glass ( I started the silicone comparison thread on here years ago). Let the whole thing cure for several days. Fill your tank and let it sit for a few days more for leak check. Youre good to go. Enjoy.
I used the MAX ACR Aquarium building epoxy.
Get your materials together to fiberglass and epoxy the OUTSIDE of the tank. Fiber glassing the outside makes for a stronger build. Let it cure for a few days. Mix and color some epoxy for the inside. Thin down the mix with acetone about10%. This will alow the epoxy to draw into the woodgrain. Let it cure (so the acetone can flash off). Sand the gloss off this first layer and roll at least two more epoxy layers on top. Set your glass ( I started the silicone comparison thread on here years ago). Let the whole thing cure for several days. Fill your tank and let it sit for a few days more for leak check. Youre good to go. Enjoy.
I used the MAX ACR Aquarium building epoxy.
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Some good advice here ^, but also some that I would use with caution. Pre-assembling the tank "dry", then re-doing it with adhesive, is an effective way of discovering errors in cutting, etc. and hopefully correcting them before permanence is achieved. These errors shouldn't exist if you have carefully planned out every cut on paper ahead of time and then executed them as precisely as possible. The problem is that wood screws...and especially wood screws that are going lengthwise into the ends of plywood laminate...are best inserted once, with adhesive also used, and then left alone. Pre-drilling all holes is mandatory! Countersinking the holes, so that the heads sit flush with the wood surface, is also a good plan, as otherwise some holes will splinter when the screws are driven. Even with pre-drilled holes, putting screws in, taking them out and then re-inserting them again is not ideal. Large pieces of wood will invariably show some bowing, which requires clamping them to hold them in alignment while you drill all those holes.
I'm not a fan of using the epoxy as the adhesive between wood pieces either, because the effective working time (pot life) of the epoxies I have used is quite short. This method will require measuring and mixing very small quantities of epoxy, which then gives you a very short time span to use the stuff. Once you have applied it you have to clamp the pieces to hold them in alignment...again...and then drive the screws. Doing so is of course going to squeeze out much of the epoxy all along each joint, and cleaning this up will be a pain, especially as it starts to set up. Perhaps epoxy as an adhesive is theoretically capable of producing a stronger joint...I honestly don't know. However, a properly-executed joint using screws combined with quality wood glue is immensely strong, and far, far easier to work with. Take the carefully measured/cut pieces, apply wood glue, hold them in alignment with clamps, and perhaps add a small number of very small finishing nails along the length of the joints to prevent bowing. You now have plenty of time to drill/countersink your hills and install your screws. The finishing nails can either be driven all the way in or, if left proud to begin with, they can now be removed.
At risk of sounding negative, there is one more thing to consider regarding the finish of the exterior. I'm sure that glassing it as suggested will improve strength, but doing so means that both interior and exterior of the wood is completely sealed. If you ever develop a leak, this can be problematic. If the leak is large/fast enough that it becomes visible as drips or wetness coming through a joint, you will be aware of it and can take steps to correct. But a pinhole leak that develops or exists in the interior surface can be exceedingly slow, being detectable only as a damp area. Leaving the outside surface unsealed makes detection easy, or at least easier, and allows the water to evaporate and hopefully not spread too far. If the water invades a piece of wood that is completely sealed on both sides, especially with an opaque finish, it can't dry out, can't be seen or felt and will eventually rot and weaken the wood completely undetected. I have had only a few leaks over many years and many tanks, and exactly one of them fell into this category. I discovered it entirely by accident, and by the time I did there was a substantial area of wood that was rotted and unrepairable. The tank was a write-off.
Lots of different opinions, lots of different construction details to consider. Think things through; plan out your cuts on paper; double- and triple-check every step as you go. Do not rush. Discover potential mistakes while still at the "Wow! That was close!" stage, instead of pushing through to the "NOOOOOO!!!!!!!" stage. And have fun! Building a tank from scratch is hugely satisfying and well worth the effort.
I'm not a fan of using the epoxy as the adhesive between wood pieces either, because the effective working time (pot life) of the epoxies I have used is quite short. This method will require measuring and mixing very small quantities of epoxy, which then gives you a very short time span to use the stuff. Once you have applied it you have to clamp the pieces to hold them in alignment...again...and then drive the screws. Doing so is of course going to squeeze out much of the epoxy all along each joint, and cleaning this up will be a pain, especially as it starts to set up. Perhaps epoxy as an adhesive is theoretically capable of producing a stronger joint...I honestly don't know. However, a properly-executed joint using screws combined with quality wood glue is immensely strong, and far, far easier to work with. Take the carefully measured/cut pieces, apply wood glue, hold them in alignment with clamps, and perhaps add a small number of very small finishing nails along the length of the joints to prevent bowing. You now have plenty of time to drill/countersink your hills and install your screws. The finishing nails can either be driven all the way in or, if left proud to begin with, they can now be removed.
At risk of sounding negative, there is one more thing to consider regarding the finish of the exterior. I'm sure that glassing it as suggested will improve strength, but doing so means that both interior and exterior of the wood is completely sealed. If you ever develop a leak, this can be problematic. If the leak is large/fast enough that it becomes visible as drips or wetness coming through a joint, you will be aware of it and can take steps to correct. But a pinhole leak that develops or exists in the interior surface can be exceedingly slow, being detectable only as a damp area. Leaving the outside surface unsealed makes detection easy, or at least easier, and allows the water to evaporate and hopefully not spread too far. If the water invades a piece of wood that is completely sealed on both sides, especially with an opaque finish, it can't dry out, can't be seen or felt and will eventually rot and weaken the wood completely undetected. I have had only a few leaks over many years and many tanks, and exactly one of them fell into this category. I discovered it entirely by accident, and by the time I did there was a substantial area of wood that was rotted and unrepairable. The tank was a write-off.
Lots of different opinions, lots of different construction details to consider. Think things through; plan out your cuts on paper; double- and triple-check every step as you go. Do not rush. Discover potential mistakes while still at the "Wow! That was close!" stage, instead of pushing through to the "NOOOOOO!!!!!!!" stage. And have fun! Building a tank from scratch is hugely satisfying and well worth the effort.
