I was wondering if anyone tried placing the FT and sump bellow ground level in order to have cooler water during summer?
I have a small greenhouse we use for raising seedlings, and it's dug about 1.5m into the ground. It was actually a swiming pool/pond at first, and we used a few extra arches from the big greenhouse to make some shade. Later we put foil on it and got an "underground" greenhouse. So I thought of digging into the side of it and placing the FT so it is surrounded by soil on 3 sides and the bottom (i would have access from one side and the top). The sump would be dug in to be under it or 1/2 lower (access from the top would be sufficient I guess). So essentially both the FT water and the sump water would be cooled by the soil, and I expect the water temp to be significantly cooler.
I live in Southeast Alabama and have a fish tank that is buried into the ground. Because of the temperatures here, It does not seem to make much difference in the summer (as far as I can tell) probably because I'm not far enough under ground. I will say though that, in the winter, I have a difficult time getting the temperature up to a comfortable level for the tilapia. The ground temp stays between 60 and 65 all winter (especially in the harsh winter we had this last year) and defied all efforts to maintain a balmy 72 or so. I don't have any other system to compare too but I hope my own experience gives you food for thought.
I've found some other people with similar experience, and other say it worked well. So I really don't know... but I will probably try it.
When we first filled the hole to make a swimming pool (it took about 5-6000 liters) we couldn't get it worm, even in the summer. I guess the water volume was to big and needed more time to heat it up.
So my hope is, if I had 2 IBC's in the ground it would be a larger mass of water that will be cooled by the soil, then the volume of the grow beds that is heated by the sun.
In my mind it has to make some difference.. But time will tell, I guess..
If your looking for ways to cool your greenhouse, I suggest you check out this brother's website:
Btw, this is my 1,000th discussion on this website :D
I feel like I should owe you a door prize or something.....
If you get some kind of cash prize for the 1,000th discussion, 20% will suffice ;)
Thanks for the info. Your brother has some usefull advice..