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DIY or made by others?

Pieter's 20 foot long reef tank <bent-glass, very nice SW>    9/12/13
Hi Bob,
<James (Salty)>
Do not know if you have ever viewed this before but thought you may be interested.  Pieter is using our Atlantiks to light this monster system.
<Did see some stills of this system that you sent along. Impressive. Am going to share on WWM. BobF>

R5: Larger Sized Aquarium (96x30x30) – 07/05/12
Hi Eric,
<<Hey Rick>>
The 375 gal Tank is in place on top of 3/4" Styrofoam and 1/2 Fir Plywood.
During the maneuvering of the tank, the Styrofoam at one corner got "squished" a bit (see photos).
I'm guessing there is a 1mm - 2mm gap between tank and Styrofoam (tank is empty). I'm thinking this will disappear once we start to fill the tank and the weight continues to compress the Styrofoam - welcome your thoughts on this.
<<It should be as you have surmised>>
Also, I've noticed what I believe are a few small air bubbles in one location near the top of the tank between the front and side panel - see picture (tank is 3/4" thick). Should I be concerned?
<<I don’t think so… The bubbles in the Silastic appear small as you say, and they don’t seem to “span” the seal anywhere. But… You could always move it outside and do a water-fill test (ugh!). Or if this tank is newly built (I don’t recall if you said so in our earlier exchanges), you could show the pic/get the thoughts of the manufacturer re>>
Here's a silly question, would there be any harm/benefit if I put another seam of silicone along the entire inside edges of the tank,
<<Depends… If the seal now is good/intact, no…the new Silastic will not adhere well to the existing. If the seal now is damaged then, yes…but you will have to cut away the existing seal and clean/prep the glass before applying the new coat to get maximum benefit. Bottom line… Unless there’s an obvious problem I don’t see that it would be worth the effort. But that’s your call…>>
and if there's a benefit, would be OK for me to stand inside the tank (190lbs) ... or should I put some Styrofoam pieces in to distribute my weight.
<<I see there is a bottom frame so I imagine the bottom glass sits a bit ‘proud’…as such, no, I would not get in/stand in this tank without some way to reduce pressure points/evenly distribute weight…I don’t think the Styrofoam alone would be sufficient here>>
Greatly appreciated in advance.
<<Happy to share… Do send pics when it’s up and running! EricR>>

Larger Sized Aquarium (96x30x30) -- Glass or Acrylic?   6/22/10
Hi Crew,
<<Hiya Rick>>
I'm in the design stage for a 96x30x30 aquarium (built into wall).
<<Neat, and is exactly what I did back in 2003'¦same size display tank and all!>>
After hours and hours of reading/research and evaluating the pros/cons,
<<Lots to consider>>
I was leaning towards acrylic (I was thinking Tenecor - we have a distributor here in Edmonton).
<<Mine is a Tenecor-built tank, I've had it since 2003. No complaints here'¦>>
But after recent readings, in particular on Jeff Turner's website (he is a strong advocate to glass), I'm having second thoughts...and Concept Aquariums (also here in Edmonton) make excellent glass tanks/black industrial strength silicone, etc.
<<There are certainly pros and cons to both. Do your research and go with what you are most comfortable/will be most happy with>>
My major concern is (as I suspect everyone's) a seam splitting/letting go.
<<Indeed (and have experienced this)'¦>>
Based on the Q&A section from your website, it occurs with both larger glass and acrylic.
<<Not just 'large' tanks at risk here>>
With modern construction methods, which has the better track record?
<<With quality construction of both, I would give the edge to acrylic. An acrylic tank will 'give' a bit more than a glass tank should there be a fault with the support structure (this is how my previous in-wall display ruptured). Regardless which tank material you choose, give much thought to the construction of a strong, level, and planar support stand designed for the material used>>
I also see comments about acrylic yellowing over time.
<<Has not happened with my 7-year old tank'¦though I have seen a couple 'older' and not as well/more cheaply made acrylic tanks that exhibited this. I suspect much has to do with the manufacturer/manufacturing of the acrylic, and the quality of the material used in the tank construction>>
Is this still a problem with the higher quality of cast acrylic now being used?
<<Not that I have heard about or experienced>>
Love the website and appreciate your feedback/expertise.
Rick Campbell
<<Happy to share'¦ Eric Russell>>

240 Gallons Of Decisions, Decisions -- 08/18/09
Hello all,
<<Greetings Shawn>>
I hope everyone is well, and finding their summer or winter (for those of you of the southern hemisphere) to be an enjoyable one.
<<So far so good'¦thanks!>>
I'm currently facing a dilemma that I hope someone can lend some experience to.
I want to build my dream reef system
<<Ah'¦a nice dilemma to have>>
and I want to combine my 2 current reef tanks (120 gallon 48X24X24, and 75 gallon 48X18X21) into a single 240 gallon system.
<<Okay'¦assuming the two systems are compatible>>
With that being said, I can't decide on what would be a better tank layout for the inhabitants that I want to combine. I'm concerned about some compatibility issues and would like to give enough space to minimize the need to exclude some of my beloved pets.
<<I see>>
I'm in a debate over whether a 48X48X24 tank or a 72X30X24 would be a better choice.
<<Mmm, yes'¦ Both are excellent designs (I do like how you have made the depth greater than the height on the 6ft tank'¦as opposed to a 'standard' build). I think maybe the location of or viewing vantage points of the system, type livestock, and/or type of reef 'niche' you wish to replicate will determine the final choice>>
My thought for the 48 inch tank is to use a center overflow to create an island with various caves and overhangs that the fish can swim around.
<<And a perfect concept if this tank is to be viewed from ALL sides>>
I'd like to use powerheads to create a circulating current around the island and would use (2) 4 ft. fixtures, with 175 watt halide and T5 lighting.
The 72 inch setup would most likely be a standard dual rear overflow design with more traditional aquascaping
<<I hope 'traditional' doesn't mean the ubiquitous 'rock wall.' There's no reason not to be (and many reasons to be) more creative, even with the 'traditional' rectangular tank>>
providing multiple small islands of rock with plenty of hiding spots. I'd need to buy a 72 inch light fixture with (3) 175 watt halides and PC lighting.
My current stock:
120 gallon - 4 inch purple tang, a male / female pair of tomato clowns, a male / female pair of Laboute's wrasses,
5 resplendent anthias (all female so far). There are various SPS and LPS corals including Acropora, Montipora, Xenia, hammer and torch corals, brain coral, and zoos of all kinds. Kind of a mixed bag of everything.
<<Ah yes'¦the typical 'mixed garden' reef [grin]>>
Two Crocea clams and a cleaner shrimp also live here. I've been blessed with little problems.
75 gallon - This tank is only 8 months old and houses a 3 inch yellow tang, a 3 inch regal tang,
<<The Regal is inappropriate for this size tank'¦glad you are upsizing>>
a male / female pair of percula clowns,
<<You may have issues combining the Clowns between the two systems>>
a male / female pair of flame wrasses,
<<Neat again!>>
and a scooter blenny. The tangs here are a big reason for the upgrade.
There is a Maxima clam and some zoos in this tank as well. I'm obviously concerned about the wrasse pairs and the clown pairs being combined.
<<Less of a problem with the Wrasses than the Clowns, in my opinion. Even should you add multiple Anemone specimens (which I DO NOT advocate here), the Maroons would and will likely claim the whole tank against another Clown species>>
My hope is that space will be my friend and theirs as well.
<<There's always exceptions'¦but I think you need another 100g or so here>>
I plan on adding the purple and yellow tangs together and if peace can't be found I'll part with a beloved pet.
<<Can be done'¦ I have five tangs from four genera in my 375g reef display>>
I'm optimistic because it worked in my LFS with a yellow, purple and sailfin tang introduced at the same time.
<<The manner of introduction can play a big part, yes>>
I know that this is somewhat open to experience, and differs from fish to fish, but any thoughts on my system design, introduction order, and ANYTHING of note would be greatly appreciated.
<<Ultimately you have to decide which appeals most to you'¦ The 4-foot square display would prove unique over most and provide for some interesting aquascaping options. The 6-foot display would prove better for the 'patrolling' fishes you have. But'¦ If you were to return the Regal Tang, I think you could get by with either option>>
Thanks to all of you for the service you provide.
<<Is our pleasure to assist>>
I'm sure you've saved many a hobbyist and many a fish with your help.
<<As are we'¦ Thank you>>
Shawn Green,
Baltimore, MD
<<Eric Russell'¦in a hot and muggy Columbia, SC>>

The Best Vendor For Large Tanks - 05/09/06 Hi All, <<Hello!>> I'm planning to upgrade from a 90-gallon to a 270-gallon tank.  I was thinking of an acrylic bow-front tank.  Can you provide recommendations on qualify manufactures of such tanks? <<Several about, but you might get a broader perspective by polling one of the fish forums (RC, Reefs.org).  For my money...Envision Acrylics (http://www.envisionacrylics.com/) enjoys a very good reputation...and my personal experience, Tenecor (http://www.tenecor.com/), provided excellent service and quality when I bought my current acrylic tank (375g)>> Thanks again for all of your prior help. Michael <<Regards, EricR>>

DIY large tank, system plans Hi: <Hello there> I would like to build a tank out of glass and plywood that measures approximately 132" length x 36" deep x 48" high. I have been trying to locate DIY plans for a similar sized tank in the 1000 gallon range, but have been unsuccessful. Do you know where I can find plans, or anyone who will draft custom plans to my specifications? <Mmm, nope... have seen ads for such plans in hobby magazines over the years... in the back, classifieds... You could easily piece together what's involved from a cursory reading of WWM, other sites... The height is a bit of an issue... I encourage you to consider switching the width dimension... make the system three feet tall, four feet wide... to save on the viewing panel cost, make it easier to work on, in> I am quite capable of building a tank myself, but I do not have the engineering knowledge required to design such a tank. Thank you in advance for any assistance you can provide. Rob Koblasz <What aspect/s are you wanting input on? Width of materials, modes of construction? Plumbing, filtration? Gear? Bob Fenner> 
Re: DIY plans
Bob: <Rob> Thank you for both your time and reply. I guess I have quite a few questions relating to both the materials and the mode of construction. Is it better to use glass or acrylic, and how thick should it be? <Either might well be preferable in different settings... likely the glass will be less at the shorter height, the acrylic easier to work with (much, much lighter), but scratch and bow more easily...> As for the plywood, is 1" marine plywood sufficient? <If braced, screwed every four inches, fiberglass strip and resined in the corners, for the three foot height, yes> Is steel reinforcement necessary for the dimensions I would like? <No> I have an acquaintance with 2000 gallon tank that is 20' in length which was built with steel reinforcement every 2', but I do not know if it is necessary for the tank that I want to build.  <Not necessary, but advised... especially in an area subject to ground movement...> I have researched your site and others as you suggest regarding DIY tank projects and I do have a rough idea how to do this. With regard to the height of the tank and the changes you suggest, are there any structural concerns, or just cost and ease of maintenance? <Quite a few structural concerns... know that for every foot of height such projects about double in cost... in materials> I believe taller tanks are great for viewing, and floor space might be a concern with the extra foot of width. <Mmm, I'd do this... make a "cardboard mock-up of the shape/size of the proposed system/s... the three and four foot width/height dimensions, and stand it up in the proposed space... the three foot tall one is very likely the route you want to go...> I sincerely appreciate any additional information you can provide as I do not want to make a mistake I will regret when the tank is full. It makes for a much happier wife when the water remains in the tank. Thanks Rob Koblasz <I understand this... as well as the (extreme) possibility of the thing coming apart, perhaps killing someone. Bob Fenner> 

Building a large plywood tank 8/9/05 Hello all! I first want to thank you all for all of your time and effort in helping all of the aquarists in need of info. It is so greatly appreciated. Thanks! <Thanks for the kind words!> Before I start I would like to say that I have read every posting on WWW to do with tank building and construction. (phew, a lot of reading!) I have also scoured Ozreef.com, Garf.com and the internet in general on the subject. <Great!  Lots of good info!> I would like to build a plywood and acrylic tank with the dimensions of 96" width x 36" depth x 36" height. I was going to use 1" plywood for the frame with a 1" thick acrylic window. The front piece of plywood would frame the acrylic 3" around all sides. I was all set until I went to my lumber yard to get the plywood. After talking to the rep and telling him what I was doing, he informed me that the strength of plywood has more to do with how many layers the plywood has than it does the thickness. He told me that 3/4" plywood with 10 layers would be stronger than 1" plywood with 8 layers. He also told me that hardwood plywood would be stronger than softwood plywood. He had some 3/4 inch birch plywood that was 10 layers.  <Let me begin by saying that I am not an engineer and I have never built a plywood tank (I have built/repaired acrylic and glass tanks).  I should also admit that I am not a fan of the idea of plywood tanks.  If there is any way for water to find it's way to the wood, it will.  Once it does, the wood will swell, fasteners will rust and the problem grows.  IMO, the risk of this is too great to justify what will probably turn out to be a smaller cost savings than it seems.> 1) Could I use the 3/4" birch plywood or should I stick with my original plan and use 1" exterior grade plywood? If I go with 1" plywood, could I get the same strength by gluing two 1/2 inch pieces of plywood together. (My lumber rep tells me that the glue bond would be stronger than the plywood itself) <Your lumber rep is probably right... the strength of the plywood probably has more to do with more layers than absolute thickness (within reason), but also has a lot to do with the type of wood and the type of glues used.  These types of questions should really be directed to a structural engineer.  In any case, I would definitely use dimensional lumber ribs/spines to add strength and rigidity to the plywood and coat the entire structure in a marine grade epoxy or fiberglass after proper surface prep and priming (do you see the costs mounting?<g>)> 2) Is the 3" border for the front frame enough to hold the acrylic viewing pane in place or should I make it 4"?  <I would guess that 3" is enough, but not if it is made of unsupported plywood. Even if the border is well secured to the adjacent bottom or side panel, it will support relatively little pressure, especially if it gets wet.  I would want at least the bottom perimeter to be supported by dimensional lumber (wide side down, so it couldn't "roll") that was anchored to the same sheet of material that formed the bottom of the tank.  This would prevent the sides from being able to "blow out".> 3) Instead of using plywood top braces (which would block some of the light going into the tank), could I use 1" thick acrylic braces that would be drilled and screwed to the plywood frame? How wide would you make the top braces?  <Tropicorium in Michigan uses wooden tanks in their greenhouses.  They support the tops with steel cables or threaded bar covered in garden hose to protect it from the water.  This is very strong and block almost no light.  Drilling and screwing through acrylic is risky because acrylic is "Notch Sensitive".  Think of scotch tape... it is very strong if you pull on it, but if you nick the edge, it tears very easily.  Small holes drilled in acrylic act like the nick in the edge of the tape.> 4) I actually plan on making the tank 37" high. The extra inch will be on top to accommodate the 1" thick top braces. (nestled in between the front and back walls)  The water column will still only be 36" though. Is this ok? <Yes, but calculations should be based on the depth of the water.> 5) Instead of coating the inside plywood with resin or epoxy, I was thinking of using thin acrylic sheets (1/8") to cover the bottom, sides and back. I figured once I had the front  1" acrylic viewing panel siliconed to the front, I could use the thinner acrylic and  bond it to the front piece and then bond all the other acrylic pieces together. This in effect would create an acrylic box inside of the plywood box.  <This is a great idea, but you would still have to coat the plywood to protect it from moisture (even if it is protected from frank water contact).  Also, if moisture did swell/warp the plywood, it would easily crack the thin material allowing gross water contact. All this brings us back to the issue of cost.  I suspect that if you add up all of the costs of the acrylic, plywood, acrylic adhesives, etc. that your savings would start to shrink.> 6) Is the 1" thick acrylic enough for the front panel? Can I go thinner? Should I go thicker? Thanks so much for your help.    Mike <1" is thick enough if it is adequately supported.  A couple of cross braces should do it if the top edge is beefy enough (I would think 4x4 lumber or maybe even angle iron).  www.cyro.com has a thickness calculator that you can use.  Sorry for my pessimism for your project, but spending the money on a tank built by professionals is cheap insurance against 450 gallons of water on your floor and a tank full of dead animals.  If you do give it a whirl, good luck!  AdamC.>

Even 300 Gallons Can Be "Small" - 08/22/05 Yes, I know. The Yellow and the Naso were rescues from a poor vendor in Toronto.  I am surprised how well they have done. <<me too>> My fiancée and I are building a new house and we are incorporating an Aquarium room. <<sweet!>> I am having a 300 gallon acrylic tank made for one wall by a company in Minnesota. <<Getting closer.>> It will be the main display reef and I am thinking of using the 180 as a seahorse and kelp setup. <<Very nice.>> I don't think the tangs will grow too much in the next 9 months. <<No...likely due to developmental retardation...>> Thanks again. Ps. Do you know of anyone who has made a reef out of a swimming pool? I thought this could be a nice project to have a 20000 gallon system under a greenhouse so that one could swim with the display.         <<Have heard of such, more recently a new construction discussed on RC...and once saw pics of a 7,000 gallon outdoor "lagoon" system with a giant viewing window in the basement(?) wall of a home in Hawaii...fabulous!  Regards, EricR>>

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