Backyard Aquaponics
A place to discuss aquaponics

A promised, here are a couple pictures of our "work-in-progress"...

Rubbermaid, (Redneck Hottub) TM
I knew there was another use for those tanks.
Looks like a pro conversion.
Dont you dare let that GB fall on your toes!
Nice.

They have a 110 volt instan hot water heater on ebay for $169.

The water would be cooled down by the time it went through the GB's and into the sump tank. It might have a temperature setting, I would have to look up the spec's.

LOL.....I will put some concrete blocks under it when I get all of the kinks out of the system. I had these laying around, so I used them. Not much chance of the GB falling when loaded.

i see why my calcualtions are not very good, I calculated from the numbers on the diagram and the GB are narrower on the bottom than the top. I understand better the 50 gallons of GB volume.
Id o agree with your system now, specially when the 400 gallon FT will be in place.
Don't forget that you will have to calculate your fish load on the growbed and not on the density in FT, because of the disproportion in between them.
With 100G GB, the fish load at max for a starting system like yours will be around 20 kg of fish at high stocking.
It will then be a fish load of 0.2 kg/G, which is low fish farming wise.
The only way of increasing the fish load would be to do regular water change when the nitrate readings are very high or to get some solids out before being decomposed by bacteria.
Maybe you could find a way of having planted buckets added to the system and use them to use the water from the water changes and keep plants inside.
A few solutions that you'll have to play around in a few months anyway because the fish load will increase slowly since I suppose you'll be starting with fingerlings.
What specie of fish are you going to grow?
And what kind of plants?
Thanks for the pics, makes me travel in front of my computer.

We have a pond on our farm, about 1/3 of an acre, that has been stocked over the years. In fact, many of the fishermen close by would fish the pond before we bought the property. We plan to use the water from this pond, as it is already conditioned for our area, and we plan to take fish from the pond since they are conditioned for our area. The pond has three main varieties; bluegill, bass and catfish. The bluegill are the most prolific of the three, and if allowed to grow large (such as in captivy), are the best eating (white meat, nice filets, etc.). The bass are nice too, and produce the most meat per fish. We will not mess with the catfish though, too much trouble. So we will probably try both, and see which one works the best. I am going to try to catch them with a casting net so that we can have a full range of ages, which we hope will allow us to fast forward the system several months. As for the plants, we will start out with leafy vegetables, tomatoes, cucumbers, peppers, etc. I am working on a verticle bed design in my head after seeing some of the pictures on this site. I have a 8 foot section of wall that is 8 foot high that would be perfect for some of those GB's made out of PVC pipe. That is phase three though. We might also put some low-volume drip beds using regular flower pots and.....shh, don't tell anyone..... dirt!

I am going to have to re-think things a little. After double-checking with the feed-store on the capacity of the second FT, I will need to add an additional FT to the system. Basically, I would have the 150 gallon FT and two 200 gallon FT's, plus 50 gallons worth of sump tank. That will teach me to run with the math before checking the measurements. Basically, I will be running a 600 gallon FT system, with the two large GB's and the vertical wall and a few individual pots. Am I still okay with everything???

This brings up a question. The sand filter is rated for 15,000 gallons at full pressure, as it is made for swimming pools. If I were to run the water through filtered, it would filter the solids and algie out of the water. The nutrients and bacteria are microscopic, right? Am I correct in thinking that I can run the water through the filter, or should I bypass the filter, or run a special filter run once per week? What are everyones thoughts on this?

As for the fish, I will using a large fish (6-8 inche) bait cage to catch my fish in our natural pond. Since I will be starting out with pretty large fish, and basically as many as I want, I have more questions.

1) Once I get the system totally cleaned out, I planned on draining the water, and replacing it with water from the pond. My question is, do I need to use 100% pond water, or can I use say 50 gallons pond water to 100 gallons regular. It would be county water which might have bad things in it I guess, that could hurt the bacteria. What would be best?

2) How many fish should I put in the first 150 gallon FT? Should I start small at first, then add more to avoid startup problems?

3) I need some help in figuring out what kind of test equipment I will need to ensure that the tank water is healthy for the fish, nutricious for the plants?

The farther into this thing I get, the more questions I seem to have....

First of all, the sand filter is not to be used because it will really reduce the amount of organic material in the system. The nutrients and bacteria are microscopic ,yes but the nutrients come from the organic material (fish poo) and the ammonia the fish release by digestion and breathing.
As long as you can change a part of the water you won't have to take any solids out of the system.

If you have the opportunity to do all the system with pond water I would go for it, specially that you'll be able to change a bit of water every so often if the nitrate levels get to high and since the growbeds are small compared to the FT volume but enough to be good biofilters but not sufficient to have a total nutrient uptake by the plants.

The sand filter would be usefull and recommended to filter the water coming from the pond.

Second point is start low with the fish while the system cycles and since you can get access to fish easily, try putting a few more fish every week once the system is cycled. This will increase the bacteria colony in a nice and steady manner and will keep you out of water quality problems that most people encounter when getting a whole batch of fish in a system (ammonia spike, nitrite spike, disease breakout by the stress of the unstable water quality)

The number of fish in the system depends on the weight of the fish, aiming at 20 kg for 150 gallons first would be good to set the system. Once the system is going fine and you are monitoring the nitrate levels, you could then increase it to 40 kg I suppose and that is the max for the 150 gallon system and will need very good managing of the water quality by water changes and a good plant growth. This is calculated for 6kg/100L or around 12 lbs/22 gallons and this is the maximum a very good APer can get too. I would suggest to start slow and learn and see if you can get up to it after a while.

How will the towers be? If they are full of gravel and the driping always at the same spot, you might have a crap crust forming itself on top and reducing the DO lower in the tower. You could plug them on the outlet of one growbed, who would then act as a filter and increase the dissolved nutrients and decrease the solids amount in the water prior to going in the towers.

Do you know what are the optimum temperatures for the fish you're going to keep, because heated water could be to hot for them. Check the infos on the fish at www.fishbase.org.

Heating the water would be good if it is properly regulated, you could have the fish have the summer growth all year. the other problem i can see is to get the fish weaned on pellets.
Try to feed the pond with pellets and see if some fish come and eat them. It would be easier to wean the fish in the pond than in the tanks because they could jsut pick a few pellets and continue eating normal wild stuff. It would get them trained better and the time schedule would be longer than having fish in tanks not eating at all.

To finish, the test kit is an aquarium testing kit, you need to test pH, ammonia NH4, nitrite NO2 and nitrate NO3. You can find the complete kit with all the test in it. A thermometer can be usefull too.

And don't forget to think of a backup air pump or water pump.
Hope all this helps you sort stuff out.

A few questions.

1) Are you saying that I have more fish tank than I need (i.e comment on GB volume compared to FT volume) such that the GB's will not be able to use all of the nutrients?

2) The towers will be horizontal, with the flow going into one end, and out the other, starting with the top one. I had intended to put a screen on the first input hole to catch any solids, allowing for easy cleaning. Would this resolve the problem you identified?

3) I was really, REALLY, hoping to avoid the water changes, but I suppose I can do it. My method for transporting the water from pond to garden, is a 50 gallon drum in the fron-end loader of my tractor. Is 50 gallons enough to properly dilute the system? The process I would follow would be to run the filter for about 10 minutes, then backwash/drain 40 gallons or so, then put the new water in the tanks, then run the filter for another 10 minutes. Would that be a workable process?

I'm sorry to have confused you with all these explanations, it was not what i wanted at all, i just wanted to expose some information adapted to your system. Here are the answers to your questions:

1) This is exactly what i wanted too explain in the first comment on ratios, the best ratio in between the growbed volume and fish tank volume is 2:1
The volume of growbed is twice the volume of fish tank.
So for 150 gallons of fish tank, you'll need 300 gallons of growbeds.
Actually your two growbeds of 120 gallons each will be just enough for your for 150 gallons fish tank. I suppose that with the towers the ratio will be perfect. To have the 400 gallon tank going you'll be needing 800 gallon of growbeds. Might have to wait a bit for it to be used...

2) i suppose that it could be a good solution, but i don't think you'll need to clean it, it is just to have smaller solids flowing in the towers.

3)Anyway you will have to do top ups of water volume. It is better to use pond water(if it is not polluted) or rain water in these kind of systems, it is easier than conditionning tap water to inactivate the chlorine compounds.
The process you have planned would be fine.

The water changes will not be necessary if you only keep the 150 gallon fish tank.
The water changes were necessary if you used the two 200 gallon fish tank with the growbeds you had planned.
The growbeds you have now can't be enough for the extra 400 gallons of fish tanks, to use them you will an extra 800 gallon growbed volume. To give you an idea, each 200 gallon extra fish tank would need 3 growbeds like the ones you have now (approx 360 gallon in total volume).

hope this makes it clear this time

The ratio of FT to GB is all relative to stocking densities of your fish. Did I miss something?
...scratching my head

Very true, John. However, I think Amaca is just trying to get the system proportioned nicely. Amaca mentioned stocking rates earlier, although looking back, there may be a units problem.

Max stocking rates for an expert are 1 pound fish in 2 gal of water with 4 gal of growbeds. I would start with a target of no more than 1/2 pound fish in 2gal water with 4gal growbeds. Initially stock with only a couple fish in 100gal until the system cycles. Then slowly add more fish. Since you are catching your own, you could work your way up a couple each week if needed. Many of us have no choice but to dump in 100 at a time.

Ahh, ok I see.