Backyard Aquaponics
A place to discuss aquaponics

I have been reading a lot about methods of getting iron into the water.
Methods ranging from as easy as OBO's rebar in the growbed, all the way up to the "Really Smart Guy" filter.

My question is, if I used the dozen or so (expired) household gas cylinders clogging my yard, and cut them into growbeds,
would there be enough iron transfer from the steel, or would there be too much, (Can you have too much )
The tanks are only galvanized on the outside, so they should rust up nicely.
Probably need to replace them in a couple of years, but I'll have more by then.
Smelly residues are easy to get rid of, once the cylinder is cut open, just light a fire in it!

Is it worth the effort, or am I wasting my time?

I have to cut them up anyway for the scrap man to take them, so it just changes the way I cut them.

Dicko

are you talking about 190 and 210kg cylinders?

Cutting them lengthwise would make a not bad growbed not sure about the shallow bits at the sides though.

Can't answer your iron transfer question though,


take one for the team

Thanks for the support

I was planning to only slice about a third off one side so that the bed would "Belly" outwards below the top giving a bit more media / Filter volume.
It will also a give a bit more root space/depth, and strengthen the bed.

It means i only get 1 growbed per tank, but as i said, I've got heaps!

It will add iron to the system when anerobic pockets form, if there's carbon to feed the bacteria. Cast iron is the best for doing this, as it is FULL of carbon, and iron. I would be mildly concerned about Iron Oxide or rust in the water, I've been told by aquarium ppl that rust is bad for fish, but then, they think lots of AP stuff is bad for fish.
Iron Oxide is the problem chemical I would think.

Is there anything else in the steel. They do add a lot of different stuff when its made. And I'm not sure what is in the wields. But it might be worth a try, maybe in a fish less cycled system to see what happens. If it's not working give them a sand blast and paint.

Too much iron will lead to phosphorus deficiency so you may exchange one problem for another

Exactly my point

Gas tanks are made of High carbon steel

Is this good?

Welds are done in a way that will create minimal effect on the inside of the tank ("S Butt" for those that know), A zig zaggy bit with a weld at the unexposed section, Guess the gas company didn't want any corosion in the wrong spots

Ive cut dozens open in the past to make patio heaters for mates, Family etc. There is nothing inside but bare metal, and to paint that would defeat the pupose to some extent, But if there is too much iron... then paint is probably a GOOD idea, Paint the top half and leave the bottom to rust

I've got several mates that are registered PyroTechnicians!

How much should I order

Problem now is... How do you get it all to land back in the growbed ... Green side up??

Dicko

give it a go, take one for the team

Any more thoughts?

i think go for it. they're scrap anyway.

the phosphorous deficiency should only be a problem if you have too much dissolved Fe in the water. i dont think thats gonna happen at ph 7.5. Iron oxide might as well not count as its in suspension. would be cool to see how long they last fore before rusting out. maybe leave two bare and coat the rest, incase the oxidisation is faster than we think. atleast you'll have some functioning growbeds left that way.

got a plasma cutter? Mmmmmmm plasma..................

I would have kilo's of buried mild steel in my growbeds, and I am adding more to the new beds.

Burn the galvanising off, and go for it. Just make it easy enough to remove from the system once they do (and they will) rust through.

Actually, the galvanising is on the outside, so probably just leave it there.