Backyard Aquaponics
A place to discuss aquaponics

Hi, Bodgy

I looked at your tank set up and it seems too pretty to be digging a ditch all around it.
A ground rod would do just fine and be a lot easier to hide.

Look up "Lord Kelvins Thunder Storm" on you tube. That will give you a good understanding of what
dripping water is capable of. We need all the splashing to get oxygen into the water, but that
sets up the conditions to generate static electricity. with enough capacitance the static E can
build up to even lethal levels.

I have a 9ft dia plastic tub sitting on moist soil so that makes a pretty large capacitor.
then I have 12 towers around the rim,Stonehinge style then 3 minnow tanks all draining back to
the main tank, so my static problem builds up quite strong. I've even toyed with the idea of setting
up a proper system and see just how much power I could draw off....another day maybe.


anyway, have fun and stay safe Daucie

Just had a look in AS3000 (wiring rules), which has requirements for "Fountains & Water Features"and "Swimming Pools and Spas". it lists 30mA RCDs as protective measures against voltage gradients, as well as metal grids connected to the equipotential bonding.

It does appear to provide an 'out' for double insulated devices (i.e. most pond pumps), as only devices requiring an earth require all extraneous conductive parts in the 3 wet zones to be equipotentially bonded to the earthing conductor.

That said, I think its good practice to do as daucie rose does and get everything (you, 'ground', water, metal work etc) on the same potential to avoid any tickles or worse. I've been getting 'wound tickles' in my system so will bond it all together as a precaution. switching off pumps before sticking bits of yourself in the water is also a good idea and generally listed in most reputable pump manuals.

Thanks Daucie, My system ain't pretty yet though. It's only building wrap to shield from the sun so far. Luckily my soil isn't hard and at around 600mm deep it's sand so I shouldn't have a problem beating a copper pipe into the ground for an earth. I'll put some reo bar in it if it isn't stiff enough to belt in.
And I know what you mean about static, at work we had a pile of insulated roof panels and we were peeling the steel facings off to reuse them. (They were polyurethane cored with colorbond sheets as facings, maybe 7M long). The bloke I was working with suddenly jumped back and complained about getting zapped, I just laughed at him for being a wuss and we kept on working down the stack.
Well, it turns out that stack of panels was quite the capacitor, I copped a belt a minute later and I reckon it was at least as good as the electric fence around my mate's stallion paddock.
Thanks for the advice, you too Mattyoga. I really want a safe setup and peace of mind is worth the effort.