Backyard Aquaponics
A place to discuss aquaponics

also i think the thinwalled black stuff MAY be recycled material, not virgin, so anything goes.

yep

Do you reckon if enough people want it here, we could get them to do a special run using only black virgin poly?

Hi Steve,
Hydronic committed to memory
Iguess i went on the lines of water not being compressable and likened it to a hydraulic system.

Still unlikely to be rated food safe at those high temps. Stu checked about blue line (the stuff used for plumbing) and go the answer that could not be guaranteed food safe at temp. I reckon it would probably be okay - but it is too thick anyway.

hex, i'm no expert, but i'm fairly sure that all the systems have expansion tanks in them to allow for expansion/contraction due to temp chance, otherwise it probably WOULD be a hydraulic system

VB,
why do you need really high temps?
Pool heaters gain a few degrees per pass but move a lot of water through the collector, a hot water heater moves less water but attains a much a higher temp.
The amount of btu`s gained will be the same. Transferring the energy to a big tank of water would result in the same temp rise.
The hot water heater system will have more losses en route making it a bit less efficient.

I don't want to have to run a pump all day.

Ahhh, that makes sense

I am guessing that there is probably more soluble bad crap in commercial fertilizers or your average backyard garden dirt than would be leached out of black poly retic pipe.

Probably - which is why I don't use commercial fertilisers adn grow everything organically. I do feel kinda bad about what is probably in the commercial pellets I use. Will go to something organic whenever I can.

i think i may have cracked it....and all it took was a fire, lol
I was thinking about how it would be nice to pipe the warmth from the burning stump (in the way of my ap system) when i remembered something........

Last year i visited a barra farm Up St Kilda Way, and saw an interesting way of heating the water:
There was a big 2000+ Litre tank of boiling (or near boiling) water (looked like it had just some big kettle elements in it) Sitting on planks directly above the tank were the big blowers. The air pipes from the blowers went into the hot water tank before going into the barra tanks. No other heating was used in the barra tanks, and they were turning out i believe 100 tonnes a year. There was alot of aeration in the tanks due to the high stocking densities, and the bio media being big corrugated plastic sheets in the water with the water being circulated with an air lift, but it worked it was very hot and humid in there.

(i wouldn't have imagined that this would have worked very well but i have seen that it does)

In not sure how efficient it would be, but if we are running aeration anyways.....
So how about having the black poly pipe filled with water (or any other liquid...) with an airline running through it, and then the black poly coiled on the roof or in a grid, etc with the liquid just sitting still......

I reckon she'd have to be a fair sized airline.. I send to agree with your thought that efficiency may be an issue. The heat that does not get taken from the air into the water would be lost wouldn't it?

Sorry Daniel ... you've lost me there?

yeah probably unless it was enclosed like in a greenhouse.......
But if the bubbles were fine enough maybe the heat (due to the large surface area to volume ratio) would be dissipated into the water and just water temp air released

Will go see if i can find info on the actual system, i believe it was sweedish made