Backyard Aquaponics
http://byap.backyardmagazines.com/forum/

A somewhat complicated question about a coldwater aquaponics
http://byap.backyardmagazines.com/forum/viewtopic.php?f=11&t=23336		 Page 1 of 1
Author:  ortaparmak [ Oct 25th, '14, 07:27 ]
Post subject:  A somewhat complicated question about a coldwater aquaponics
Hello All,

I’m new to forum. I hope I’m posting to right section and not breaking any rules here –cut the newbie some slack, I’m new here :)

So, here is my question: I live in Kiev, Ukraine, where winters are typically minus 10 to 15 degree Celsius and may drop down as low as minus 25 degree Celsius. I have a half-isolated balcony (which means I have a balcony covered with glass and wood frames with lots of holes and cracks, resulting lots of warm air escape and lots of cold air enter; so basically it just prevents the wind factor). I’m putting a 400 liter acrylic water tank in there –plus my 120-liter aquarium as sump- and transferring my 120-liter system (which has one starlet fish, about 50 cm) in to 400 liter tank, and about 6 baby sterlets in 120 liter aquarium –to be moved to 400 liter acrylic tank later as they grow. So there will be total of 520 liters of water in the system. With outside temperatures ranging between minus 5 to minus 10 daytime and minus 10 to minus 25 nighttime, (and given that the sterlet are cold water fish), what would be the wattage I’d need to keep the water ust above freezing (i.e. about 2-3 degrees C).
Another thing is: water will be transferred between acrylic tank (400 liter) and glass tank (120 liter) via one inch (2-3 cm diameter) PVC pipes, so what is the best temperature to keep water from freezing inside the pvc pipes? Sterlets are kind of sturgeons and they love cold water (as long as it is still water and not ice). :)
Author:  Titus [ Oct 26th, '14, 00:47 ]
Post subject:  Re: A somewhat complicated question about a coldwater aquapo
Hi
This is not really an aquaponics question .It is a physics question.
My home freezer keeps food at about -18*C
So I am guessing about the same power requirement as a home freezer.
Only in reverse!
Obviously improving you insulation will help.
Titus
PS Hope you and your family are safe.
Author:  scotty435 [ Oct 26th, '14, 15:18 ]
Post subject:  Re: A somewhat complicated question about a coldwater aquapo
Clear plastic or bubble wrap could help with the air leaks if it's available.

Most of the aquarium heaters I've seen around my area are for tropical fish and their thermostats would try to keep the water temp higher than you want so they'd always be running. I'm not sure what you can get there. If the balcony is close to the outside temp it will get extremely expensive to heat the water.
Author:  ortaparmak [ Oct 26th, '14, 16:43 ]
Post subject:  Re: A somewhat complicated question about a coldwater aquapo
Titus wrote:
Hi
This is not really an aquaponics question .It is a physics question.
My home freezer keeps food at about -18*C
So I am guessing about the same power requirement as a home freezer.
Only in reverse!
Obviously improving you insulation will help.
Titus
PS Hope you and your family are safe.



Titus Hi, and thank you for your answer and your good wishes. Actually, I'm interested in heating the water not the balcony so I was hoping maybe someone with similar experience can give me an idea from their practical experience in similar conditions. Because sterlets are coldwater fish and the balcony will be very cold, I don't think aquarium hobbiests can help. So I decided to give it a try here.
Author:  ortaparmak [ Oct 26th, '14, 16:44 ]
Post subject:  Re: A somewhat complicated question about a coldwater aquapo
scotty435 wrote:
Clear plastic or bubble wrap could help with the air leaks if it's available.

Most of the aquarium heaters I've seen around my area are for tropical fish and their thermostats would try to keep the water temp higher than you want so they'd always be running. I'm not sure what you can get there. If the balcony is close to the outside temp it will get extremely expensive to heat the water.


Good point. I never thought about the preset temperature setting that most heaters have. Perhaps I can get around that by setting the thermostat to its lowest setting and putting it on a timer (to run only a few hours during night)...
Author:  scotty435 [ Oct 27th, '14, 02:32 ]
Post subject:  Re: A somewhat complicated question about a coldwater aquapo
If you put it on a timer there is a chance the water will freeze when the timer has it shut off. Probably not real likely but possible. There are some people who've built their own heaters and also some information on thermostats to use them here on the forum. There is a very interesting thread, on another forum, about making your own here and if you dig through the thread it has different versions of heater and it points you to a thermostat as well - http://community.theaquaponicsource.com/forum/topics/diy-heater-build-your-own-2000-watt-heater-for-20?id=4778851%3ATopic%3A246637&page=1#comments

I haven't looked at the thermostat but I think it works on water temp not air temp.

I can't vouch for the safety and I haven't used one but many people do. I heat the air in my greenhouse using a space heater and thermostat. It doesn't have to run much but is still like throwing money out the window :)

All of these require that you have access to the parts or something similar where you are. The more you have to heat this tank, the more expensive it's going to be so insulation is your friend.

Hope this helps
Author:  ortaparmak [ Oct 28th, '14, 01:33 ]
Post subject:  Re: A somewhat complicated question about a coldwater aquapo
scotty435 wrote:
If you put it on a timer there is a chance the water will freeze when the timer has it shut off. Probably not real likely but possible. There are some people who've built their own heaters and also some information on thermostats to use them here on the forum. There is a very interesting thread, on another forum, about making your own here and if you dig through the thread it has different versions of heater and it points you to a thermostat as well - http://community.theaquaponicsource.com/forum/topics/diy-heater-build-your-own-2000-watt-heater-for-20?id=4778851%3ATopic%3A246637&page=1#comments

I haven't looked at the thermostat but I think it works on water temp not air temp.

I can't vouch for the safety and I haven't used one but many people do. I heat the air in my greenhouse using a space heater and thermostat. It doesn't have to run much but is still like throwing money out the window :)

All of these require that you have access to the parts or something similar where you are. The more you have to heat this tank, the more expensive it's going to be so insulation is your friend.

Hope this helps


I am now thinking about spending the next weekend to repair the isolation and install a small room heater on timer to keep the balcony around plus 10 C (instead of experimenting with water heater / timer set up)... which would let me use the balcony as a greenhouse too. And it certainly sounds less complicated :) Thanks for all the information.
Author:  scotty435 [ Oct 28th, '14, 05:05 ]
Post subject:  Re: A somewhat complicated question about a coldwater aquapo
That should work but keep in mind Winters here in my part of Oregon are much warmer than yours :thumbright:

You might be able to insulate pretty well and maybe use a layer of rigid styrofoam insulation on the floor. Watch the weight of the system and make certain the balcony can handle it, water isn't light.
Author:  ortaparmak [ Oct 28th, '14, 05:12 ]
Post subject:  Re: A somewhat complicated question about a coldwater aquapo
Yep, the weight worries me too -especially relevant in this Kruschev-era apartment building (I saw some balconies collapse in similar buildings on the internet) :) soviet engineering. in soviet russia, buildings engineered themselves

I read on the internet sterlets do fine in frozen water -as long as it doesn't freeze in to a big block of ice- and I don't think that could happen to 300 l water overnight. I would definitely see the surface freezing and have time to take measures -at least so I hope.
Author:  Leblackstock [ Nov 9th, '14, 22:23 ]
Post subject:  Re: A somewhat complicated question about a coldwater aquapo
Just a question that is somewhat relevant here. Has anyone used pond de-icers? The ones that keep the surface just above freezing?

Lauren
Author:  scotty435 [ Nov 10th, '14, 03:24 ]
Post subject:  Re: A somewhat complicated question about a coldwater aquapo
I haven't used them but found this thread helpful - http://forums2.gardenweb.com/forums/load/ponds/msg1109365815072.html
Page 1 of 1 All times are UTC + 8 hours
Powered by phpBB® Forum Software © phpBB Group
https://www.phpbb.com/