large plwod tankers a few ?s

[greatgman001]

hii all out there
as the thread sayes
im considering making a large ply tank (300 g)
and would like to ask for any detailed shots of the construction
such as side reinforcement, upper and lower front panel thickness and width (wooden)

also what i was thinking of to seal it with swimming pool liner or pond liner, contact cemented to a later of pink insulated foam, that in turn is contact cemented to a sanded and sealed plywood;
not sure if marine grade ply should be used.
also to ofset the cost of 1/2 inch safety glass or starefire i was gonna use 2 peices of 1/4 plexi siliconed together at the edges to give me a 1/2 in plexi front.
what do u think?

 

[mflamb]

There are some threads here with all you are asking for. Do a Reef Central search.

 

[thriceanangel]

check this out:
http://fingerlakesreef.com/forum/viewforum.php?f=13

 

[BeanAnimal]

The swimming pool liner is not a good idea. It will degrade over time, but even if it does not, the chances of puncture are fairly high. The foam will exacerbate the problem.

Pond liner could be used but creating a good seal at the Glass/rubber interface is going to be tough. You will also have the problem of what and how to tuck the corners to get them to look good, not to mention the overall look of black pond liner for the inside of the tank.

2 pieces of plexi that are NOT fully laminated will not offer the strenght you are looking for. They will also tend to show a gap between the two pieces as they flex. This will be in the form of a shadow and/or distortion due to reflection and refraction.

The time tested way to do this is to use the proper thickness of glass or acrylic and to line the plywood tank with a fiberglass reinforcment and resin. A top coat of resin or epoxy paint is used for the finish coat. The top coat SHOULD be NSF certified.

Total Plastics here in Pittsburgh can get the cell cast 1/2" or 3/4" plexi. The 1/2" will cost less than $300 for a 4x8 Sheet and the 3/4" less than $400. I have not priced glass lately but it should be reasonable for 1 pane.

Epoxy paint that is NSF certified will run a little over $100 a gallon. Fiberglass cloth is cheap and you can expect to use $200 worth of bondo and bottom coat resin.


Bean

 

[AcroSteve]

Is there a proven method or interior coating that will allow repeated scrapings of coraline algae without damage to the painted surface?

 

[BeanAnimal]

"proven" I do not know. Glass cloth and resin can be pretty darn tough, as can some 2-part epoxy coatings. I would think with proper surface prep, a 2-part coating could be very durable as long as the same precautions used for acrylic are followed.

 

[AcroSteve]

I'm a glass man, and as far as I can see, that is the only big downside to plywood tanks.

I sure like taking a razor blade to the glass and cleaning it up fast.