My First System! (Plan)

[Adam Jensen]

First off, this board is the BEST!  I tuned into aquaponics by accident.  My daughter loves looking at the fish and lobsters in the grocery store tanks, so I started googling about the possibility of raising fish in my own tanks.  This is how I found you all!  I love organic locally grown foods, and you can't get more local than the small greenhouse attached to the south side of my house.

 

Living here in the Niagara region of Ontario, Canada (Zone 6a), we get hot summers and cold winters. Being in the fruit belt, we also have lots of places to purchase used tote tanks and barrels that were previously used for oils and fruit concentrates.  I based my system on a 1000L (275 ga.) tote tank - top removed - and three 23" by 3' plastic barrels, halved lengthwise.  The tote is $100 and the fixed lid barrels are $10 each.

 

My goal is to run this system off solar, and so I'm going with a 12V DC pump.  When next fall comes around, I will be adding some LED light panels to help extend photosynthesis during the shortened days.  My rationale for insulating the grow beds and tank is to help mitigate some of the seasonal temperature fluctuations which will lead to the system becoming too hot in the summer and too cold in the winter.  I also plan on running tank effluent across the surfaces of all three beds (rather than trickle down from top bed to bottom bed) to increase the surface area of bio-filtration and to ensure similar concentrations of nitrogen on all tiers.  The tank will be stocked with Rainbow Trout, since I can source fingerlings nearby and also since they are adapted to the cold winters here.

 

 

I plan on building this next month, once this terrible cold snap passes.  I would love to hear your input on this, as I have probably overlooked a few details.  

 

I would also like to have your input on how many trout I should attempt in this set-up, as well as the potential use of redworms in the grow beds.  I'm looking forward to sharing my photos as it all comes together!

 

All the best,

 

Adam

 

[TCLynx]

How many barrels will be set up?  Are they already cut?  Will the pump be running constantly?  Will the barrels be flooding and draining or just trickle through or constant flood?

 

Barrels cut the long ways require extra support and are harder to get auto siphons balanced in, cut round the middle they are easier to support and get siphons to work in.

 

For 275 gallons of fish tank I would be aiming for about the same volume of grow beds if not twice the volume of grow beds but that might require a sump or indexing valve if you are running flood and drain.

 

Trout need good water quality and good aeration.  You need to move the volume of the fish tank each hour minimum.  I worry that a 1600 liter per hour pump might not deliver the flow you need.  As it it might pump 1600 liters per hour but only at 0 head with no pipe friction losses.  Once you pump above the surface of your water and do it through small pipe like 1" CPVC you may not get anywhere near 1000 liters per hour.

 

I use a 4000 liter per hour pump on my 300 gallon system.

 

And how many trout to stock.  Well after the system is fully cycled (look up fishless cycling for a low stress method) you might stock about one fish per 7.5 gallons (or one cubic foot) of media bed (I'm assuming flood and drain or constantly flow/flood) for your first season.  So if it is only 3 half barrels as filtration, then around 10 trout.

 

However, if you are only trickling the water through the gravel beds (no flooding) then you will get far less filtration even if you are doing pretty elaborate distrobution grids.  In which case you will only be able to support a far smaller number of fish without adding some other form of filtration.  I highly recommend constant flood with a stand pipe and plenty of flow through the grow beds in your situation, might not be quite as good for the plants as flood and drain but is definitely better for bio-filtration and I've seen trickle through beds fail to provide much meaningful filtration at all because the water tends to channel and most of the media stays dry unless you spend most of your days cleaning and shifting the distrobution grids.

[Adam Jensen]

Wow!  Thanks for your input!  There is a ton more to think about!

TCLynx said:

How many barrels will be set up?  Are they already cut?  Will the pump be running constantly?  Will the barrels be flooding and draining or just trickle through or constant flood?

 

Nothing is cut as of yet.  I was planning on using a constant flood of water through the hydroton (but your recommendations helped reinforce the need for this)

 

Barrels cut the long ways require extra support and are harder to get auto siphons balanced in, cut round the middle they are easier to support and get siphons to work in.

 

Very good to know.  This would have been something that I would have only discovered myself after the media was in... the sides started to buckle outward, and half the hydroton dropped into the tank, lol.   I will most certainly change my plans and cut the barrels around the middle.  Doing this would allow me to increase my grow bed capacity as well as I could get more into the cramped space.  I'll need more barrels and see if I can get close to 500 gallons of grow beds.

 

For 275 gallons of fish tank I would be aiming for about the same volume of grow beds if not twice the volume of grow beds but that might require a sump or indexing valve if you are running flood and drain.

 

Since the system is going to be solar, I wanted to avoid using a sump pump if possible.  I should have enough capacity to add an additional submersible 12V pump though.

 

Trout need good water quality and good aeration.  You need to move the volume of the fish tank each hour minimum.  I worry that a 1600 liter per hour pump might not deliver the flow you need.  As it it might pump 1600 liters per hour but only at 0 head with no pipe friction losses.  Once you pump above the surface of your water and do it through small pipe like 1" CPVC you may not get anywhere near 1000 liters per hour.

 

Also very good to know.  The pump will have enough head, but I didn't consider the losses due to pipe friction and gravity.  I'll get a second 12V pump which will increase my flow to 3200 liters per hour.

 

I use a 4000 liter per hour pump on my 300 gallon system.

 

And how many trout to stock.  Well after the system is fully cycled (look up fishless cycling for a low stress method) you might stock about one fish per 7.5 gallons (or one cubic foot) of media bed (I'm assuming flood and drain or constantly flow/flood) for your first season.  So if it is only 3 half barrels as filtration, then around 10 trout.

 

However, if you are only trickling the water through the gravel beds (no flooding) then you will get far less filtration even if you are doing pretty elaborate distrobution grids.  In which case you will only be able to support a far smaller number of fish without adding some other form of filtration.  I highly recommend constant flood with a stand pipe and plenty of flow through the grow beds in your situation, might not be quite as good for the plants as flood and drain but is definitely better for bio-filtration and I've seen trickle through beds fail to provide much meaningful filtration at all because the water tends to channel and most of the media stays dry unless you spend most of your days cleaning and shifting the distrobution grids.

 

I'll rework the volume of grow beds based on your suggestions and see if I could get 20 trout into the tank.  continual flow/flood method seems ideal based on the experiences so I'll go with that.  

 

Thanks for taking time to share your expertise!!!

 

Adam

[TCLynx]

Very good!  Yes increase your filtration and flow and you should be in far better shape for trout at least through the cool seasons.  Once you get through your first couple seasons you will be better able to figure how many fish you can add beyond what you have planned.