Heating an IBC

[Dusty Greggor]

Hi Guys

I have just started my outside AP system. I have 3 grow beds above a 1000L IBC fish tank.

Where I live it gets down to about -5 Degrees C in winter.  I have about 200 Blue Tilapia in the tank.

All is fine at the moment, I have two 300x heaters in the water and it maintains at 27 degrees C.

But winter is not far off, can I have some ideas on how best to keep the water about 20C during winter.

I have the IBC insulated with roofing insulation and is standing on a sheet of polystyrene on the floor.

The system is in a greenhouse. Would it be better to keep the greenhouse heated to above 20 than trying to heat the water?

[Vlad Jovanovic]

Hey Dusty,

Many companies make IBC Heating Jackets...from passive jackets to ones that consume 1800Watts...it might be worth looking into. Honestly though, it seems like maybe choosing a different type of fish might be a good way to save a lot of cash on electricity and heating accessories...but if your dead set on tilapia, here's a place in the UK that sells both IBC heating jackets and heaters...http://www.heattracing.co.uk/product-details/ibc-heaters-%7C-ibc-he...

[mario cole]

I'm thinking about keeping the chickens on top of the tank... they can keep each other warm and cool... depending. Maybe in a greenhouse.

[Chris Carr]

200 Tilapia in a single IBC tank system sounds like too many. How big are the grow beds? How many cubic liters of media total?

[Dusty Greggor]

Guys thanks for your responses. I will certainly look into the heating jackets Vlad.  Yea ideally changing to trout or koi would be great, but I have these little guys (fingerling size) that are won't nearly be big enough to harvest before winter. So gotta prepare now for the cold.

Chris, they're only very small at this stage and when they do start to get bigger, I have another two IBC's on standby

If the three IBC's are in use when winter arrives I was thinking of a rocket stove heating a 55 gal drum of water with copper pipes in the water going to sump for the fish tanks.

Only problem is the fire would pretty much have to burn throughout winter.  Am I on being silly or would 2 500w aquarium heater per IBC work?

[Chris Carr]

Ah... good about the standby tanks but there are standby grow beds too correct? tank size is not really that important. growbed filtering capacity is. Also keep in mind as the media gets colder, the bacteria ability to process ammonia also decreases greatly.

A member (http://aquaponicscommunity.com/profile/RickStillwagon) recently was testing out a pellet stove for heating IBC tank(s). I am not sure what your conditions are specifically but I would think that insulating the tank very well is worth the investment over more wattage in terms of heaters but still not sure if 1000w is enough. Also keep in mind the grow beds themselves can influance the water temp a lot. When it is cold, you may want to try constant flood over flood/drain to minimize the media sucking all the heat out of the water as it is filtered.

Dusty Greggor said:

I have another two IBC's on standby

[mario cole]

I use a 1000w bucket heater to heat the spa up, its about the same gallon wise as an IBC. In fact the built in heater only uses 1000w in 120v mode. Its fairly well insulated though and it takes several days to warm up in our 40-50 degree winters.

[Vlad Jovanovic]

Keep in mind that you don't want any water that has been in contact with the copper getting into your system (or your heating might be all for naught). Rick's pellet stove (really cool btw) I believe uses some sort of exchange mechanism so that no copper is ever in direct contact with any system water.

As far as "is 1000Watts enough" it really depends on your delta-t....How cold the water is, how cold the surrounding air is and the temperature difference that you want to achieve (and of coarse volume of water). Unfortunately when you design these things out you usually need to design them for the most extreme situation that you expect to be in (which sometimes seems silly to invest and pay for all that, for an event that may happen to last less than a week out of the year, but if you don't...you might (probably) get screwed...

There are some charts from AES I have lying around somewhere which might help give you an idea of sizing out the heaters...if you don't already have something like that, I can dig them up for you...

[Dusty Greggor]

Ahhhhhh Of course, I forgot the fundamentals Vlad. Thanks for reminding me.  I cant use hot water going through copper pipes heating the fish tank water, because dem fishies deh don't like copper  :-)  

Wow that pellet stove looks awesome, I'm certainly going to play with a few ideas.

I'll keep you informed.

Thank you guys, you saved my brain from getting fried thinking of idea to do this.  Very helpful. 

[Vlad Jovanovic]

Hey Dusty...just one more thing to think about in reference of your OP...

"...The system is in a greenhouse. Would it be better to keep the greenhouse heated to above 20 than trying to heat the water..." ?

If the air in the greenhouse is colder than the water in your fish tank(s) you can pretty much look forward to lots of condensation...which may do funny stuff like freeze the greenhouse door shut so that you cant get in there (hasn't happened to me personally, but apparently has to others)...freeze on metal gutters making them expand/contract possibly blowing out/cracking the glass near the gutters (like what has happened to me...though not from any fish tank water)...So, yeah IMO it would be good to keep the air about as warm as the tank water or a bit warmer...

[Dusty Greggor]

Never even thought about that side of it.  Thanks again Vlad

[TCLynx]

The water might make a handy thermal mass for the really extreme times but yes, you want to warm the air and insulate the greenhouse to an extent if you really want to keep tropicals growing through winter.  I've seen some greenhouse lean to or A frame designs that have the reflective boards that can lay down from the greenhouse by day to help reflect more light in and then you flip them up to insulate the greenhouse as evening comes on.  This is great provided you are always home at dawn and dusk and can be there to close up before snow piles on them.

I'd personally say try to switch over to a more temperature tolerant fish.  I'm in FL and tilapia are still to heat intensive for me.

[Dusty Greggor]

Thanks TC. Florida and Tilapia are still an issue?  Wow, I should be so lucky as to have your problems  :-))

Thanks for the advice I'' certainly look into some reflective boards.