All steel tank...DISADVANTAGES

[dlobom]

But if the tank inside surfaces is seeld from the water then there should be no problem......i think.

Oh and sorry i should of said




a MILD STEEL tank, not ally or stainless steel.

Then you must really treat the surface against corrosion, specially along the welded parts, thats generally where it starts.

A good layer of anti corrosive primer and latex paint should not only protect it, but also insulate it pretty well. Maybe some lead free marine paint.

 

[Burtess]

Mild steel????

Forget it... I don't care what you do to it, after a couple of years it would look like crap and probably be rotting out.

You would have to use stainless (316 would be a good one (expensive)) to make it last.

Burt

 

[The1and only]

I looked in to building my own steel fish tank, and what killed it for me was the final cost. To seal it properly was going to be over five grand to have a local ship yard do it. I was looking at using the same company that seals the water tanks for Navy ships.

 

[Danger_Chicken]

sounds like a bad idea to me. There are several reasons not to do it and I can't think of one positive reason to do it. If you are going to paint it like a wood tank than why not just do a wood tank?

 

[boredinthepeg]

I could see doing the frame in mild steel but the tank itself would definately have to be stainless. Can get away with 304 stainless for freshwater and I would never bother using any metal for saltwater. Even 316 tends to develop pinholes within a couple years when used to hold saltwater. One other downside to a metal tank is any surface scratch will end up with iron deposits from the water and will turn red. We seal all our s/s tank frames with a clear coat just to prevent surface deposits.

 

[waynes world]

Ok its a bad idea, worth a look though, i would of had the whole inside treated with a pond sealer type paint, even maybe a few coats of fibreglass to seal the steel from the water.

I am now going back to looking into a steel frame and ply/grp lined tank, much prefer steel as a frame than wood, i can do the fab work no probs, and cost of the frame is coming in at around £350 for 3x1.5 channel, with 1/4 inch wall. Could get the frame galvanised or zinc painted, the cheaper option would be taken there

I havnt said so edit here

The tank wil be either 10 or 12 x 6 x 4.

 

[earthstudent]

You could build the tank of mild steel and have it powder coated. There are some powder coatings that is basically a layer of plastic melted to the surface of the metal.

I am a welder/metal fabricator by trade. I own my own side business building stuff out of metal. I am a well experienced welder of all processes and metals. I will tell you the main concern in building a tank in the 500g-2000g range is going to be distribution of the pressure evenly over the metal support structure without acquiring to much weight, cost or being complex, over just building with wood. Steel is stronger than wood no doubt, but is very flexible as well. When you design a tank of metal you will find that going all metal is just not a good idea, definitely doable just not that practical in the normal home built tank sizes.

Building a basic metal frame lined with wood is on the other hand a good idea if you are trying to save space as you can make a support frame just as strong as wood but take up less space. Lining the tank with metal is the main weight factor. If you go to thin it can tear at the welds and if you go thick enough you will end up with a tank much heavier than it needs to be.

If you are going to hire a welder to weld it for you than forget about it, it will cost you 5 times more in the long run over just building it yourself out of wood. Metal is only really useful if you are going much bigger.

How big are you planning?

 

[waynes world]

I am going through all ways that i can build this, from poured concrete to this, as you will know i will loose even more space with a concrete, either poured or block.

Thank is going to be either 10 or 12 x 6 x 4 (around 1400g uk), i can weld it myself as i have a mig and have welded many a thing, used to build trailers as a side thing and build 4x4 off roaders, i guess that as my axles never fell off when off roading my welding aint to bad LOL.

My idea is the use the 3x1.5 spaced at 24 intervals around the sidea, 4 cross members front to back along the base and 2 90 degreees to them. and maybe some 1/4 angle around the base about 12 inch up for added support at the base, plus a bit more when i get the desgn sorted.

wayne

 

[earthstudent]

That size tank is more realistic if you are going with a metal frame. I still think wood would be the better all around option at that size but metal will work out just fine.

The way I would build it is... 3"x1.5" with 1/8" wall rim, top and bottom of the tank with vertical supports (2"x1" 1/8" wall) every 12-14". Like a wall frame. Like this but metal...

No need for cross bracing on the tank. If you are building a stand than depending on the design you might need cross bracing on that. You will want one "cross brace" to go across the middle of the top rim of the tank, due to the length of the tank.

**Just so you know, you could build a tank to your dimensions, like the one shown in the picture and it would be plenty strong. No need for metal. I am going to be building an 8'x8'x4' tank in the future, that I plan to build just like this one with just a couple small changes.**

I would still go with plywood on the inside. If you wanted all metal, you could go with sheet metal but I would not go any thinner than 16 gauge, 14 would probably be best. You would need to stitch weld the sheet metal to all the supports. You will need a decent welder and have some decent skill to do this and you will still get lots of warping in the sheet metal that you will be pounding out.

If going with plywood on the inside (3/4"), I would drill and counter sink holes (in the wood) for machine screws that go through the plywood and vertical supports and lock nut on the other side. You would not need allot of these, just enough to hold the wood firmly in place.

To protect the metal you could have it plated (several options there) or powder coated. You could also just clean it up and paint it with Rustoleum paint yourself.

 

[Lepisosteus platyrhincus]

there was a member that made a stainless tank. expensive has heck.

i personally have considered building a frame out of steel. That way i could bolt it together to make it moveable. The entire inside would be granite. Like a granite counter top. Have them gruve it so it snugs together, and bead the creaces with silicone. Would be beautiful and anble to be taken apart and reassembled.