Ready to make the plung!

[plantwomyn@verizon.net]

I've been studying for months now and it's time. Just purchased a 22 x 30 greenhouse with roll up sides. I am going to set up a small commercial aquaponics system.
Here are my ideas:
I want to make the greenhouse passive solar. It has square bows making it easier to install foam insulation between and along the North wall.

I want to start small and do a study on how much product I can grow. I'm going to start with a wall unit with stacked 4" pvc. along the 30' south wall. Hope to make it look allot like Laurie's NFT system.

I have a source for tilapia and maybe trout so will have to make a fish choice soon. I got 1 300 gal. and 1 150 gal. used rubbermaid tanks for 150.00 us. Not too bad.

So once I get the greenhouse set up (1 month) have a pretty good idea how to set up my starter system.

Big questions I have are:
Is the 4" pvc okay? I'd like to build everything myself.
Do I need to buy an expensive ph, oxygen tester or can I just go with a cheaper aquarium set for now?

I want to be able to grow in our Indiana winters so would it be better to set growing trays in the ground or can I use above ground units? I will be building them myself either way.
I've seen mention of wood stove and solar water heating systems. I think Murray talked about a copper tubing system he's using. Can anyone help me with a SIMPLE design for one? I get allot of sun even in winter but I have wood and propane heaters.
Those are my immediate questions for now. Any help ya'll can give me will be much appreciated.
You're website has already been a great find and great inspiration.
Thanks
Dianna

[Murray]

Welcome Dianna,
You are embarking on a very exciting project!!! The greenhouse sounds great.
FishFood will be able to comment on heating for winter, he lives further south that I do and has dealt with much colder winters. (I don't think as cold as yours can be)
You will need some way of removing solids from the water before passing the water through the NFT tubes you are proposing. A simple way of doing that is to run the water through a gravel grow bed first. That will act as a bio-filter and you will be able to grow some veggies in that grow bed as well.


NFT - (Nutrient Film Technique)With the NFT (also known Nutrient Film Technique) technique, the plants are grown in channels (also called gullies) which the nutrient solution is pumped through. The plant roots are kept moist by the thin film of nutrient solution as it passes by. Ideally, the bottom of the roots are exposed to the nutrient solution while the top are kept moist but not water-logged.
Most NFT channels are fed continuously at a rate of approximately 1 liter per minute. Since the plant roots are not in a growing medium, it is crucial that they are kept moist at all times. In most NFT systems, the nutrient solution is mixed in a primary reservoir, cycled through the channels and back to the reservoir. With the development of on-demand dosing equipment, a nutrient reservoir can automatically be adjusted and, with proper aeration and pH adjustment, can effortlessly be kept fresh for weeks at a time.
NFT is ideal for lettuce, leafy crops and herbs, all of which are short term crops. Larger NFT channels are used for long term crops such as tomatoes and cucumbers in many locations around the world. One great benefit of NFT, especially for leafy crops, is that with no growing medium and no soil, the crop is clean and no washing is necessary. Growers, chefs, grocers and consumers all appreciate this.
NFT channels are usually set up on waist-high stands that slope slightly to allow the nutrient solution to drain to one end. Although round pipes have been used in NFT production, most growers have found flat bottomed channels or gullies provide greater surface area for root development and oxygen uptake, resulting in better, faster plant development.
See http://www.aquaponics.com/InfoHydroponicMethods.htm

See also http://www.ias.unu.edu/proceedings/icibs/ic-mfa/adler/paper.html
This is a good paper on the subject.


The difficulty you face in getting good information is that using NFT in Aquaponics is different to using it in Hydroponics. The difference is in finding ways of dealing with the solids produced by the fish. In hydroponics this problem does not exist, well, not to the same extent anyway.
You may need to adopt some of the techniques used by aquaculture projects such as swirl filters and settlement tanks. If the solids are not dealt with clogging will occur after a time.
I have a small 40 plant NFT table that is working fine, but the water from the fish tank passes through some small gravel filled pots first to remove some of the solids. I notice towards the middle of the growing cycle the plants at the "in" end are doing better that the plants at the "out" end. The root growth is big at the in end which restricts the water flow to the out end . I feel this is because of the remnant solids trapped and used by the lettuce roots. The plants downstream do not get as much nutrient. There is a lot of good stuff in that solid matter from the fish.
I hope this helps a little, and please keep us posted on your progress.
Murray

[GaryD]

Hi Dianna,

Prior to my current job, I worked as a business development consultant for several years.


I want to start small and do a study on how much product I can grow. I'm going to start with a wall unit with stacked 4" pvc. along the 30' south wall. Hope to make it look allot like Laurie's NFT system.

You're wise to start small. If you can't operate a small system, you'll be unlikely to succeed with a large one.

Have you considered how easy it will be to operate (and harvest from) a system consisting of stacking 4" pipes? It's one thing to have such a small home-based system but how practical is it for commercial application?


I have a source for tilapia and maybe trout so will have to make a fish choice soon. I got 1 300 gal. and 1 150 gal. used rubbermaid tanks for 150.00 us. Not too bad.

It's one thing to be able to source fish.....but it's much more important to have somewhere to sell them. Make sure your markets are in place before you commit too much money.

We Australians tend to envy you Americans for the fact that you have Rubbermaid.


Is the 4" pvc okay? I'd like to build everything myself.

Your preferred crop (the one for which you hopefully have a large market) should drive your choice of growing system.


Do I need to buy an expensive ph, oxygen tester or can I just go with a cheaper aquarium set for now?

I have an expensive pH tester but it doesn't provide consistent readings......so I use a test kit that I bought from a pet shop.



I want to be able to grow in our Indiana winters so would it be better to set growing trays in the ground or can I use above ground units? I will be building them myself either way.

I've seen mention of wood stove and solar water heating systems. I think Murray talked about a copper tubing system he's using. Can anyone help me with a SIMPLE design for one? I get allot of sun even in winter but I have wood and propane heaters.



If you tell me more about the climate in Indiana, I can probably be of more help.

Gary

[fishfood]

Hi as far as heating goes if you have plenty, wood is cheap but more labour intenseve i use nat gass [just set and forget] if possable for your winters try and double skin the glass house [cos it talkes a lot to heat on a cold night]

[plantwomyn@verizon.net]

Norther Indiana is a zone 6 and goes down to -10 F in winter.
I have a 50,000 btu nat. gas heater but I want to heat water with it too. Can I set up copper coil like you guys talked about in - Re: Extracting waste heat from central gas heater flue. Silly?
How do I do it and can anyone send me pictures of such a unit?
I was also thinking about trying to set up some kind of radiant heat through the gravel beds. HELP!

I'm starting with lettuce and culinary herbs. I already have a couple of restaurant owners interested in produce and tilapia.

[GaryD]

Hi Dianna,

Here are a few suggestions for optimising fish growth (and survival) during your winter extremes:

Install your fish tank inside of the greenhouse - the water will get warmed up during the day.
Cover your tanks at night.
Do you have central heating inside of your house? Consider growing fingerlings inside in a small tank or aquarium. Once they have outgrown your inside tank (and the weather has become milder), they can be moved outside into the greenhouse.
Can I set up copper coil like you guys talked about in - Re: Extracting waste heat from central gas heater flue. Silly?

Not silly at all. Your plumber is the best person to advise based on your circumstances and local regulations.


I was also thinking about trying to set up some kind of radiant heat through the gravel beds. HELP!

I'm not sure what you mean here......can you elaborate?

Gary

[plantwomyn@verizon.net]

The radiant heating is actually root zone heating. check out www.trueleaf.net (http://www.trueleaf.net) and look at their micro climate heating . Very Cool. I've talked to them and they tell my I would need a 100,000btu boiler for a 4'x25' ebb & flow bed! The tubing would be in the gravel BTW. I thought 100,000 would radiant heat a whole house! Believe it or not I've got one but it sounds like overkill to me. Not a HVAC geek so I'll have to talk to my heating guy. I figure the ambient heat from the bed should help heat the greenhouse too. What do you guys think?
I had a brainstorm and thought I could set up a tank less electric water heater and run 1/2" pvc through the beds to heat it. They say no way.
The greenhouse is 22' x 30' Gothic, covered with poly. I intend to insulate the North side with foam.
I'm worried that if I try to get things started in the winter (it's 50F today) I will end up losing fish and plants without enough heat. I can live with growing just cool crops (lettuce, spinach) for now but how about my fishies?
I can start them inside but our winters are 4 months and I know they'll grow to big for the house before March.

[plantwomyn@verizon.net]

Thank you Murray for downloading my design. So from the explanation of the flow from one bed to another, bo you think I can get away with only two pumps? I've read some threads about pumps but still can't get my head around how much power I will need.
I will need a sump pump to go up 7' and I have a Little Giant 5 MSP-WG and it's rated @ 1200 gph and 26' max. head and a Hayward 1 hp pool pump that is 115 volts. I have read that the gph goes down the higher that you pump. So I'm still unsure if the sump will keep up with the flow (drain) from the beds.
I have also read in threads that a 1 to 1 ratio is best. Does that mean I need one cu. ft. of fish tank to each cu. ft. of bed? If so I may have too much growing space for my tank to support.
My tanks are 1 300 gal. and 1 150 gal so 425 gals. of capacity if they aren't filled to the top.
My beds measure-
D-4x20x1=80 cu. ft.
B-3x20x1=60 cu. ft.
C 3x16x1=48 cu. ft.
A-2x20x6"=20 cu. ft.
So about 170 cu. ft. since beds are not filled to top.
170 cu. ft. = 1275 gal. of water.
Obviously the beds are not going to be full all at the same time.
When A fills to a 2" from top it flows into B and so on.
D flows into sump pump.
So is the Hayward too powerful or too expensive to run to use to pump the water from my tank to my bio filter? As you can see(I hope) from the design from the bio filter the beds get feed by gravity. I'm actually thinking about using my Doughboy pool filter for the bio filter too. I'd take out the sand and put in filter material. I'll have to tweak the amount of water flow with a shut off valve at the entrance of the bio filter cause the pump was for a 24' pool and moves water!

So maybe I'm just slow but I can't understand the ratios of pump power to grow beds to return pump.
Can anyone help?
Also could use a step by step on how to install a drain on my beds. I've seen some pics but again too slow to get the jist.
Thanks again for all the help.
I'm about to start pounding posts for my greenhouse hoops.
Lots of work for an old lady!

[Murray]

Hi PlantWomyn,
You have put a lot of thought into your proposed system. I feel that you have incorporated a load of good ideas into your system. Aquaponics is beautiful if kept simple.
The gravel grow beds act as a bio filter, so the bio filter you have incorporated into your system is not really necessary, but they are a useful addition to a system. Generally they help polish up the water and keep it sparkling. I use one from time to time mainly because I have a lot of people coming to see my system and they like to be able to clearly see the fish.
Pumps. Yes pump performance dorps off the further and higher you want to pump the water. The pump manufacturer will be able to provide you with a graph of your pumps performance. My advice is to purchase the best pump you can afford and buy one with more capacity than you think you need.
The manufacturers graphs are established in a laboratory under ideal conditions, so out in the field any pump usually delivers a bit less than the specifications claim. A larger capacity pump can be throttled back a bit to suit your particular layout and will only burn the power it requires to do the job. Some folk look at the "watts" stated on the pump and get frightened by the higher number expressed on the pump. "Watts" burned is in proportion to the work done, so if you regulate a lower flow out of the pump it will burn less power in proportion to the work done. The bigger pump can then cope with any later expansion of your AP system.

I use a 3500 gph pump on my system that is based on a 350 gallon fish tank (we use liters not gallons so my conversions may not be spot on)
My 15,000 lph (3500gph) pump moves the water into my grow beds, about 1000 ltrs (200 gal) of fish tank water in about 4 to 5 minutes, and then it takes about 40 minutes to drain from the grow beds back to the sump. The sump is cleared by a smaller pump, 8000 lrs or about 1000 gph pump, into the fish tank. It fires up every 5 minutes or so and runs for 2 or 3 minutes until the sump clears. It is controlled by a float switch in the 100 ltr - 20 gal sump.
I love bigger pumps......... they do not have to work as hard so therefore they last longer.

You are thinking of the beds not all filling at the same time.....how will you regulate that ?
The beds need to flood and drain in order to work properly.

[plantwomyn@verizon.net]

Per my design, once A bed fill to 2" from top it starts to drain into bed B. So by time bed B is draining into bed C, bed A will be empty. I am still trying to figure out the drains! how do ya'll get the beds to fill to a certain point then drain completely????????? I still need pics of drain plumbing. Saw some on backyardaquaponics but not enough detail for me to seee how they're plumbed.
Murray are you using timers and if so which do you recommend? Remember I'm in the US and trying to stay as local as possible.

[Murray]

Gary has had some experience with timers so he may be able to assist you on that one. I am still searching for the perfect timer.
Float switches work well on larger tanks say 350 gallon and above, but on smaller systems they can be a little difficult to adjust.

Two basic ways to drain your grow beds. I will draw a couple of pictures later on today and post them up. Have to run now I am late to get somewhere.

[GaryD]

Hi,

I'm using a timer and standpipe to control the pumping cycle on my 1000 litre system.

Setting up timers is easy. You drill holes in the base of your stand pipe to ensure that your grow beds drain within a predetermined time.....for my system is 30 minutes. The fill/drain arrangement has to be set up so that the water is coming into the grow bed faster than it drains.

I use a bypass on my pump to adjust the rate of flow that enters the grow beds. I also use a small valve on the supply pipe to each grow bed so that I can balance the flow to ensure that each grow bed fills at the same rate.

I use cheap timers that I source from my local hardware store. They switch on and off in 15 minute increments.....which are unreliable to say the least. To accommodate this problem, I drill several larger holes in my standpipe at the level that I want the bed to flood to.

Once the bed fills up to the desired level, the water overflows the weir and runs down the standpipe. This way, it doesn't matter if the timer runs for a minute or two longer than it should.

This arrangement is reliable, precise and inexpensive to set up. For my money, it is the ideal arrangement for the 800 litre to 1000 litre systems that I prefer.

Gary

[plantwomyn@verizon.net]

Thanks Gary and Murray. I'm starting to get the picture.
There's a stand pipe around the drain. There are wholes at the base and at the fill level. Depending on my fill rate, I drill wholes to regulate how fast I want the bed to drain. So do I glue the drain pipe onto the bed or is it stand alone? I am going to use pea gravel so will the gravel be enough to hold it in place? It seems llike it would be easier to clean if it stand alone.
Gary can you give me a brand name on those timers?

[Murray]

Hi Plantwomyn,
Here is a thread with some photos of the upstand that I use in my grow beds.
I can take some more photos if it will help
http://www.aquaponicshq.com/forums/showthread.php?p=1840&highlight=upstand#post1840

[GaryD]

Hi,

The brands of timers that are most likely to be available here include Arlec and HPM. I don't know if they're available in your neck of the woods.

My preferred option for stand pipes is to have the pipe removable so that you can add extra holes as part of fine tuning your pumping regime.

Gary

[plantwomyn@verizon.net]

Thanks you guys. Murray the pics are just what I needed. Now I can see how the drain pipe goes together. I'll leave it unattached as Gary says and drill more wholes as needed.
I have been thinking about the biofilter and start out without it and add it if I need it. I think I'd rather add growing beds to filter the water but I doubt I'll need to since I don't know if my fishies will be able to keep up as it is. My thing is the vegies not the fish. I came to aquaponics when I realized how many chemicals went into hydro. Hell I don't even fertilize my lawn or use Chems on my existing garden. Why would I want to pump them into my vegies?
I've spent 3 days trying to get the blue gumbo clay out of the pipes of my greenhouse posts. The previous owners land was solid clay. The stuff is like hard glue! I ever thought about shooting a 22 through the pipe to dislodge the stuff. Well I calmed down and decided that I'd just slog through and dig it out. 10 x 32" of clay! Getting close but it gets colder every day and I want to get this greenhouse up before the snow flies.
I visited a aquaponics set up in the area and didn't like the way they did things much. Fish all at the top of the tanks and very crowded. I didnt think that healthy for the fish. The greenhouse set up was funky too. Mud on the floor and pipes criss crossing everywhere. They had tomatoes in pots with gravel in them but let the water just drain into the ground. They used a biofilter, flood and drain grow beds with no gravel {floating foam}. The grow beds had no plants at the moment, they were cleaning them, and there was a lot of poop in the beds. There was gnats and algae on the poly. A big problem for a grower! Seemed like a waste to me. They could set it up to collect the water from the tomato plants and add it back to the system to help with their filtration. They did have a cool heat exchanger attached to the hot water tank to help heat their water. Doubt they're using it efficiently.
Well back to digging out clay for now.

[Murray]

That AP place you visited is not very good. Shame on them.
It is hard to imagine how it got to that state or what book they read to get started.
I like to do a bit of experimenting, but there is a limit. The fish all at the top of the tanks would be a lack of aeration.
I hope you can beat the snow. I don't have that problem , thank heavens.

[twintragics]

hi plant. I am not sure whether you intend a gravel growbed or a dwc flow thru system.
If a gravel growbed, ur bio needs to be post grow bed. Solids will be filtered by ur grow bed and bioballs etc will handle extra denitrification that is missed in ur growbed. If solids accumulate in ur bio which is NOT ur growing media, you will have big problems down the track with sludge causing anaerobic zones, leading to H2S, nitrate reconverting to nitrite etc.
If ur bio is a solids settling chamber and u pump off the top, no drama. Just make sure there is a tap at the base to remove solids.(Makes great topdressing for plants.)
Try trout rather than tilapia, you will save money on winter heating. Both are fast growers, so u may get 2 fish stock turns per year. Rainbows(brook?) grow quicker than brown trout. Your water quality needs to be higher for trout, as does DO.
Ask ur local plumber about plumbing tips. Use pressure pipe, it doesn't leach nasties into the water.
If u bury your fishtank, you should be able to run the whole system off one pump. Gravity is our friend. Good luck and keep us informed.

[GaryD]

Hi TT,



If solids accumulate in ur bio which is NOT ur growing media, you will have big problems down the track with sludge causing anaerobic zones, leading to H2S, nitrate reconverting to nitrite etc.



I have two small trickingling bio-filters which have been operating continuously now for about 18 months. To avoid any solids problem, I put a handful of worms into each one. They seem to process the wastes sufficiently to stop any problematic build up.

Gary

[twintragics]

cool solution

[plantwomyn@verizon.net]

I've been working on building my greenhouse and my connection has been on the fritz! I was thinking of pulling a false bottom on my sump to let solids fall and put the pump on top so that most of the solids will settle before my growbed water recycles to the tank. If you look at my drawing only the first bed is elevated. The rest are at ground level and the drain pipes are below ground and flow to a sump. I'll have to scratch my head for a while and try to figure out a way to drain the gunk to somewhere I can retrieve it for use. I do want to use everything from the system if I can! I am using gravel in the beds.

[Murray]

If you are passing all your water through the gravel grow beds the gunk will be left in the grow beds. The gravel grow beds are the filter. Deep rooted veggies like tomatoes love all that gunk. My grow beds are loaded with worms now....they love the gunk.
The beauty of a gravel grow bed flood and drain system is it's simplicity, no need for fancy filter schemes .... the gravel grow beds take care of all those problems that aquaculture has, and you grow beautiful veggies in the gunk from the fish tank.