Backyard Aquaponics
A place to discuss aquaponics

.....,I think , perhaps,,,it was the pumping usage NOT the switch power usage Gemmell was perhaps talking about,,,,most switches use near Zero power.
Gemmell , there are many low power usage high head lowflow rate pumps that are suitable for this idea.

No, I mean a solar panel to tell the pump when to switch on. The power generated by the solar panel is all but meaningless, just a simple way to a pump through a solar collector only when the sun is shining
...unless you can think of a better/cheaper way to do it? Would be interested in your thoughts.

Cheers

Ah, I thought you meant a solar powered pump!

It's a great idea though, power the switch with solar power so when the sun goes down the pump switches off. I'll have to think about that. I think the solar heating is a bit of a moot point at the moment, we haven't seen the sun for 3 days and the temps have barely hardly hit double figures so I think the solar heater will have to be shelved for a bit. I need a more permanant solution. I really do think I NEED a greenhouse.

Thanks for the heads up on the greenhouse film. They're all massive quantities, I might keep an eye on it and see if there are any quantities that are a little more my league. Not sure about this stuff though - i've heard of the redpath stuff before, what do we know about this stuff?

A solar panel would give varying outputs dependant on light levels,,,this may not be healthy for the relay/pump it's activating,,,yes this can be fixed with money/electroncis.
A cheap alternative is a "night switch",,,used in most buildings etc to turn on the outside lights when the sun goes down,,,just use the other set of contacts to get 'on" when sun is shining"

Greenhouse( commercial quality ) material byt he metre,,,with "at cost delivery".....
http://cgi.ebay.com.au/ws/eBayISAPI.dll ... :IT&ih=003
$22 will get you 2 metresX 7.5 metres. Postage probably $8.
Cheers

The ebay greenhouse film seems on the expensive side to me.
I recently bought some (not from ebay tho) 11.1m wide and it works out at Aus $12.42 /m.
A temperature differential switch may be a better option than a sun activated on/off switch. The panel would only pump water when its warmer than the tank by a minimum preset amount

+1 on the temp differential switch being the best option.

I guess green-house film comes in varying quality and and price,,,I know next to nothing about how to tell which one is worth extra dollars but I did like reading "triple layered".

Yeh, I'm the same - I know nothing of greenhouse film, whether 180 micron is good or bad or anything. I have heard of other users using the redpath stuff so I'm going to go for that.

I got 180 micron size Gemmell and it is pretty strong - and works well

I don't think you people properly appreciate what I'm trying to work with/against here.

Frosty morning this morn:



Water temps at about 4 degrees. Then I start noticing frozen stuff:

The top layer of the hospital tank had frozen over



And then I see this plate of water - frozen rock solid:


And then I see this:


Thats frozen







And it's frozen all the way through.


I DON'T pump overnight. My last cycle is at 8pm, so it must have been cold enough at 8:15pm last night to freeze the whole lot of it right through. How can I win against that?

Move to Qld?

Dig a hole and bury it

In those temps,,,YEP bury the thing,,,soil temp probably around 12C,grow trout.
Ormoove to Sydney, temperate climate,,grow Trout and barra.

The sump is buried. I think the ground temps are pretty cold, almost certainly less than 12. I think insulating or burying the bathtubs would be the next best thing. As said somewhere else in this thread, they're a big metal heatsink.

I can't really bury the whole thing. No wait, what I meant was; I don't want to bury the whole thing. Hopefully this is just a particularly cold snap and we'll be getting 12 and 13 degree days from here in.

Today is set aside to build a greenhouse.

It would be a lot of work emptying and burying those bathtubs.
I guess another option is to panel around them and fill the voids with styrofoam peanuts or something similarly water resistant.
You should be fine with 180 micron greenhouse film, i bought 150 micron super strength clear and its pretty robust stuff.

OMG

Cool photos though

Your only viable option will be a greenhouse.