Heating Water

[Two Jay]

How are you, Aquapons, heating your water?

[Gary Collins]

UpDate:

Turning OFF the circ. pump for 12 hrs to cover the tank at night to hold in heat was a bad idea. Maintaining 75*F was easy but the tank quickly Putrefied just over night. After a 2nd night the tank had to be drained and flushed. I noticed a behavioral change also. They stopped eating. So far the nights are only down to 58*F range. SO far no dead fish.

Will instead add a 2nd waterbed heater to see how that maintains temp over night. And no more 'offing' the pump.

 

Gary Collins said:

Here is my experiment:

I have a Tilapia Tank about 275 to 300 gallons that is circulating an over-head gravel growbed. I want to enclose the system in a lean too heated green house but until the Green House Fairy gets out of economic exile, I will make an 1 1/2" thick foam cover (jacuzzi style) to cover the tank at night while 2 waterbed heaters cook 24/7 (about 600wats), This size tank should take about 750~900 watts to heat so Im close. The circulation will be stopped in the evening as that just pulls the cold air back into the water. So far temps at night as in the 60s so no worries yet. Will up date how the Temp maintenance goes.

 

[TCLynx]

If one turns off pumping at night, you still need to make sure there is ample aeration.

What were the water tests like in the morning after 12 hours of no pumping?  Was the ammonia high?

I don't really think you will do well with not filtration at all if you are keeping the temps up high enough to keep the fish eating.  Perhaps an insulated bio-filter that you can keep pumping through overnight even if you can't keep the flow to the media beds overnight.

[Gary Collins]

Left the aerators Running, no problems. Didn't test the water, but am sure the ammonia was high. Won't stop the filtration again. I will add another heater and see how it keeps up while the nightly temps are still not to cold yet.

TCLynx said:

If one turns off pumping at night, you still need to make sure there is ample aeration.

What were the water tests like in the morning after 12 hours of no pumping?  Was the ammonia high?

I don't really think you will do well with not filtration at all if you are keeping the temps up high enough to keep the fish eating.  Perhaps an insulated bio-filter that you can keep pumping through overnight even if you can't keep the flow to the media beds overnight.

[Richard Wyman]

 

Gary, if it is possible to set plastic over your beds at night it will help, Even if it is just draped over the top and down the sides a bit it helps. I imagine a nice hoop cover would really work well.  I saw about 7 degree's of heat savings with just draping it over the top last winter. I took it off during the day when my GH warmed up.

[TCLynx]

Or Frost blanket will give protection over night and won't burn the plants if left on during the day if you are unable to cover/uncover all the time, it will cut down on the light to the plants a little but at least they won't scorch being under plastic in the sun.  You can get tension wire for fencing at lowes or home depot and make little arches that can help support frost blanket or light plastic over the plants if they are not too high.

[Stephen Corbett]

I'm going to try heating my tanks with compost this winter. I have two fish tanks approximately 450 gallons each. I just brought one of them on line very recently in anticipation of the arrival of some catfish.  I have 128 sf of raft beds and 18 sf of flood and drain medial bed. I also have a very bountiful supply of sabal palms. I found a chipper on craigslist for $100 and have made a pile of mostly sabal palm fronds that is about 10' in diameter and 5' high. I ran 50' of 1/2" irrigation tubing through the pile as I was building it. I am side streaming the water going from my sump to my fish tank through the pile. The pile is only a few days old and I got a 3 degree Fahrenheit delta when I started the water through it today.

    The big question marks for me are how much heat (btu's not temp) I can get and how long will it last. I have intentionally made the pile very carbon heavy thinking it might give me a longer slower burn though it will probably be slower to start.
     I have seen you tube videos of people heating water with compost piles but they were much larger piles and didn't offer up much in the way of details.

      I'll be happy if I can keep my fish alive through a South Florida winter without impacting my electric bill.

[TCLynx]

main thing with compost heating is that you need lots of compost and the space to work with it in and you don't usually get a slow steady long term effect.  You will probably find that you get heating for a while and then it tapers off and you have to turn the compost and add more material to get it to heat up again but even so, each successive turning will give you a shorter heating period.  Most people decide it's too much work to keep up.

 

However, if you have over 800 gallons of fish tank plus raft beds and you are using catfish (what kind of catfish?) well if they are channel catfish like mine, once they get a little bigger than fingerlings, they will survive even a central Florida winter without supplemental heating.  Granted when the water gets much below 60 F you might need to quit feeding them but I've had plenty of channel catfish survive nearly freezing water.

[James Casey Brown]

i use  1000 watt heaters they doing well for 275 gal totes 

[Stephen Corbett]

TC, On the compost heating are speaking anecdotally or from actual experience? I ask because I have read conflicting information about this and the conflict appears to be from composting to get compost as opposed to composting for heat. There are a few youtube videos showing people composting for heat and they are claiming to have plenty of heat for domestic hot water (in one case for a bunkhouse) throughout a winter and in northern lattitudes. They say nothing about turning the pile though one mentioned injecting air with a probe. The piles were massive though, as big as a house or larger. Look at some of the web info on Jean Pain.

I only need to keep my tilapia from dying for three months probably. Last winter I lost 80 to 90 percent of my fish. Also I will be getting 50 four inch fingerling channel catfish in a week.  I am on 3 acres and zoned AG so I have some room to play with. I also have a seeming endless supply of dried out and woody palm fronds that run through the chipper reasonably well. What I don't have, both in spirit and actually, is much money for electric bills. Anyway it looks like I'm going to find out if I can do this on a little smaller scale than what has been showcased.
TCLynx said:

main thing with compost heating is that you need lots of compost and the space to work with it in and you don't usually get a slow steady long term effect.  You will probably find that you get heating for a while and then it tapers off and you have to turn the compost and add more material to get it to heat up again but even so, each successive turning will give you a shorter heating period.  Most people decide it's too much work to keep up.

 

However, if you have over 800 gallons of fish tank plus raft beds and you are using catfish (what kind of catfish?) well if they are channel catfish like mine, once they get a little bigger than fingerlings, they will survive even a central Florida winter without supplemental heating.  Granted when the water gets much below 60 F you might need to quit feeding them but I've had plenty of channel catfish survive nearly freezing water.

[TCLynx]

I never actually did it myself.  I did read thought the thread as some one in OZ tried to keep an AP system warm with coils of tubing buried in a compost pile.  He eventually decided it wasn't worth all the extra effort with a compost pile that was probably less than 6 feet by 6 feet by 6 feet.  Now if you had a really big pile, it might be enough in South Florida.  See the difference between heating domestic hot water and heating aquaponic water is that the aquaponic water being circulated through the system will loose heat (especially in flood and drain beds) during cold times while domestic hot water usually sits in an insulated tank until it gets used the one time.

 

Now here in FL, I know people who will keep tilapia alive during the cold spells by simply letting water run to waste as they top up with well water since well water here comes out of the ground warm enough to keep the fish alive.  I don't like that since it is such a waste of water and my well water is too hard and keeps my pH too high but some people do it.

[aaron gallagher]

Joe did you ever get that 600' of PEX into your system? Any updates on your heating/cost predictions?

[Joe Bifano]

Aaron, I am still in test mode. Yes I have the 600 feet installed and I have the tank below ground so I am able to do nothing and keep the tank temp at 45 degrees.  I have tested it to see what it would do but have not recorded any real data yet. I have it on a variable speed taco pump and have seen it go on for about 10 minutes and it raised it 1 degree so far but becasue I do not want to pay to heat the tank with propane I am not willing to raise the temperature up yet. I have no fish in the tank so I am not quit ready yet.SO as the sun has warmed things I have it all about 50 degrees along with using some propane.

I am testing a wood stove heat exchanger and 500 gallon water storage tank. That has been tested using a wood stove and a pump on an open system and I have raised the temperature on about 200 gallons over night about 50 degrees. Soon I will be adding the tank to full and testing it again. Once I can get the tank to above 130 degrees I will be adding a heat exchanger to the closed system with a normally open zone valve from the storage tank and a normally closed zone valve from the propane heater so I use the storage tank first.  Then I will start raising the temperatures up to 60 then on to 65 slowly so I do not use any propane. I have a lot of free wood.

I live in Colorado and right now I have been using the propane to just keep things in the greenhouse from freezing. I have 2 1200 gallon fish tanks and 4 750 gallon troughs all connected with PEX along with a Utility room that is 12x32. I have only used about $200 to keep these all about 50 degrees since September. So I spent about $40 per month just to keep things from freezing and making sure they stay at 50 degrees all night long. We have had some real cold nights and so far the PEX has not broke. I do know that one time I had a frozen PEX pipe but because the pressure on these pipes are about 20 psi I have had no problems. I am not heating the greenhouse at all just the waters.

I also built a hoop over the troughs with an R-15 aluminum cover. I am testing this right now and seeing about a 5 degree difference in the temperature. Tonight I added a bathroom small ceramic heater in it and see that it has added another 10 degrees. With that info I am looking at adding some baseboard hot water heaters in the trough area. I will use the hot water again from the storage tank and see what I can get next.  I am hoping to get it too about 60 degrees so cold crops will do really good. The I put down the cover at night and raise it up at day. This will allow me to not have to heat the whole greenhouse and just the covered areas. I should save a lot.