Backyard Aquaponics
A place to discuss aquaponics

Hi Stevo,

I think you could be right about the tank insulation working against you.

It`s probably not too feasible to relocate it to the perimeter wall of your greenhouse now but if you could, you would gain some additional mass .."x" cubic feet of soil, at least to the depth of your buried tank.

Admittedly, it`s not as good as water thermally, but it should be able to store a few extra kw`s per degF temp rise

we gotta have a break through in design here...........................

I've found that its DEFINATLY the grow beds that exchange most of the heat! Doesn't matter how well you insulate your tank, if you pump water through the beds when its hotter or cooler than the tank temp you will get massive heat transfer!

Remember how cold my water was a few days ago? about 4C? we have had two beautiful days just now, todaythe temp got to about 17C i think, just checked tank temp.........14C

Hi Steve,
You`d have to thermally link the beds and the tank to the soil mass to get the most benefit otherwise what you gain in 2 good days you`ll probably lose in 2 bad ones
In stevo`s case he has a 300gal tank insulated from about 200 cubic feet of soil mass which might be able to store ~2.5kw per degF (assuming 2ft depth) or put another way, almost equivilent to having a 900 gal water tank in the same greenhouse.
The soil is sat there doing nothing so why not make use of it

yep, i agree, sort of went at a tangent.........highlighting my issue becasue my growbeds are out in the open.

Interesting... So instead of pumping water in pipe so it gets hot on a roof.. why not run water through a pipe through a growbed of rocks, without water in, instead using balck rocks in the sun, like a radiator?

ie... snake a hose through a small growbed filled with black rocks that is in the sun...

I wonder it that would heat up your water much.. you can get black rocks from bunnings

You may as well use the growbed circulation to collect and transport the heat. You`d need a lot of pipe to get the same contact area.
Bury the tank and let the heat dissipate to the surrounding cooler soil.
As the tank water cools at night the heatflow will reverse as the soil will be warmer than the tank.
Waste not, want not ..my granny used to say

Not much works as well as the thermal mass in my aquaponics building. I have 2" foam down one meter around the perimeter. The floor is 4" concrete and the tank is 4000 gallons sunk 3 feet into interior ground. So allthis thermal mass is isolated from outside. The mass reaches 70F in summer and 50F in winter. The water flows thru the plant roots warming them in winter and cooling them in summer. The thermal mass pulls against the extreme temps in summer and winter. In winter it keeps the building above 40F and in summer it keeps the building below 90F. All with no added energy. Not many things in my engineering career are so automatic and helpful and no moving parts or energy cost. Almost too good to be true!

Sorry Steve, i forgot about that.
I guess in your case any amount water heating is a plus regardless how how long it lasts

Doug, Sounds like you did a great job in the planning stages

Oops sorry guys, I've been neglecting my thread and missed the conversation. work got very very busy and I haven't checked in for a while. It's late right now so I'll post tomorrow along with an update.

-Stevo

We've eaten all the broc, cauli,lettuce and some grape tommies,cukes and celery.
It's been hot here for the past few weeks so I'm still battling heat in the GH. I've been leaving the doors open during the day. This was a mistake as the cabbage moths have found a new breeding ground, the worms have attacked my 2nd planting and I now have a grudge against anything resembling a moth. I think I solved part of the problem by replacing 2 door panels with a 3/8" mesh, the moths can't get through it but the bees still can.
My cukes were doing awesome but they started produce oddly shaped fruits and then started to die off, maybe it's the heat

water temps have been hovering in the high 70's and the fish are happy, except for one that is being medicated in the hospital pond.

Tommies are thriving as are the celery.


zuccini in the dirt


tommies almost ready


celery is rockin!



decimated broccoli



-Stevo

Love it!

Seems like only yesterday when you were diggin the hole artistic....

Cukes will grow into odd shapes if they are insufficiently pollinated. The die off if they get a mildew. If they aren't completely dead, try a 1:10 milk:water spray. I haven't used that one myself, but some folks here are saying that would help, and it won't bother the fish. In my dirt garden, I use a copper spray. Bad idea around fish.

Yep, milk spray.... works a charm on powdery mildew.... sparay late afternoon for best results.

I mixed up some milk spray tonight, I'll see what happens.
Janet, should I hand pollenate the cukes?, my tommies are fruiting just fine without my assistance.

-Stevo