ravnis system - 1 year old

[Ravnis]

I have been so busy experimenting and learning that I haven't taken the time to document my system.

The pics are from last april. The strawberry towers have since gone as they started going good and then died out. I have since added a base addition tank where I can add salt and other supplements and have it dual function as a solid settling tank.

I will have to agree with gary that solids becomes a problem when you get to a large stocking density.

I have grown 30 tilapia to 2 lbs or 1 kg since march 16 of this year. They have made some delicious dinners for me and some friends.

I have successfully bred approximately 400 tilapia. My newest concern is dealing with the cold as winter is setting in.

The growbeds are 3/4" plywood with 2x12's for the walls and lined with pond liner. I am still working with flood and drain though am considering switching to continuous flow as the bell siphons get iffy from time to time.

The IBC now feeds 2 of the growbeds. I do not have a picture of the other growbeds. Will have to try to get some more and update.

I just removed the tomato plants, they were in the black buckets and grew to 8ft plus tall, referred to them as my tomato jungle. I yielded around 200 tomatoes. Not a really good yield considering around 20 plants.

I still have to work on getting the suplementation down as I get lots of vegetation growth, but was not getting much fruit till I supplemented with epsom salt about 1/2 cup to 1000 gallons.

THe system holds 500 gallons in the blue stock tank, 250-300 gallons in the sump which is everything under the growbeds and 250 gallons in the IBC for around 1000 gallons give or take some. The sump level fluctuates.

The black garden hose is my make shift solar heater. All in all I don't feel I did too bad growing 400-500 fish in my first year considering I had almost no experience in either gardening or aquaculture before coming across this site.

[GaryD]

Hi Ravnis,

A good report.


I will have to agree with gary that solids becomes a problem when you get to a large stocking density.

Don't worry, mate......you won't be the last person to arrive at that conclusion. The list of fishkills grows by the day regrettably..... and it's all about water quality.


have grown 30 tilapia to 2 lbs or 1 kg since march 16 of this year. They have made some delicious dinners for me and some friends.

I'd really like to get hold of one or two tilapia.....just to get a sense of how good they are too eat.


I have successfully bred approximately 400 tilapia. My newest concern is dealing with the cold as winter is setting in.

Have you contemplated going to a straight recirculating aquaculture system using a relatively small fish tank and a trickling bio-filter or two? Couple that with a HPS or metal halide light and you could grow a few plants indoors and use the waste heat from the lights to keep the fish tank at a sensible temperature.


I just removed the tomato plants, they were in the black buckets and grew to 8ft plus tall, referred to them as my tomato jungle. I yielded around 200 tomatoes. Not a really good yield considering around 20 plants.

I've found that it takes time to settle a system down to the point where it will grow fruiting plants successfully. Think about pH as a factor in terms of nutrient availability. See here (http://www.microponics.net.au/?p=364).


All in all I don't feel I did too bad growing 400-500 fish in my first year considering I had almost no experience in either gardening or aquaculture before coming across this site.

I think that's something of an understatement. You did exceptionally well. The fact that you've grasped the water quality message this early augurs well for your future aquaponics endeavours.

Gary

[nwestwood]

In my system, which is about your size, I've found that I need regular supliments of iron, calcium and magnesium to get the tomatoes and cucumbers to set and grow fruit. But when I do, boy are they prolific. I add 2 tablespons of Calcium and Magnesium at least weekly, and a tablespoon of chelated iron whenever the water doesn't have a redish tint.

[Ravnis]

Have been supplementing with greensand(iron/potassium) and epsom salt and potassium chloride for some extra potassium. Have been adding the supplements when I see yellowing on the leaves.

Oh, I forgot to mention I have worms in the growbeds... so much for the worms will take care of the solids argument( I had really hoped that one would work.)

I did notice that in my aquarium I hardly ever find solids when I vacuum up the gravel. THe main difference is that the ph in the aquarium has settled down at 6.0. I made a thread about this in aquaponics IDeas. I'm theorizing that at a ph around 6.0 there will be a dramatically different solids accumulation. Time will tell. It will take some time to get the ph from 7.6 to 6.0 without shocking the bacteria and fish.

[Ravnis]

I added a very simplistic solids separator. I have a no-holes siphon that drains to the bottom tank. I put it in a 2 inch pipe to let the pipe control the water level in the fish tank. Solids accumulate at the bottom as the siphon only goes in it 1/2 way. This drains into a small trash can that I had put the rest of my lava rock I had left over. It only covered about 3 inches.

I then put some polyfiber like you buy to fill pillows or dolls with to act as a filter. This has been helping a lot. As the top layer gets absorbed with solids, I peel it away and put it in the worm bed. I discovered today when I went to remove some more that worms had migrated from the rocks into the fiber.
In the worm bin the fiber was full of worms too. THey seem to love this stuff. Might be a way to collect the buggers as I was easlily able to grab a small handful and add to the growbeds.

[Ravnis]

some pics of heater system

The heater is a portable propane tankless water heater, the hose in the tank is pex hose I found at Home Depot. I use heavy duty water hose to run from the heater to the pex hose in the fishtank. I use a portable sprinkler pump to push the water, the main reason is this particular heater has a safety that wont come on if the water pressure is blow 50 psi. I use a 32 gallon trash can as an expansion tank. The inlet hose and outlet hose in in the trashcan . The pump sucks the water out and the end of the hose returns it to the trashcan.

I will have to do some major rethinking of the system as far as insulation. There are holes under the greenhouse that let cold air in. It has been pretty expensive to heat this system this winter. I will have spent close to 1000 $ US. This was keeping the water at 70F since november. I use a temperature controller to cycle the pump on and off. Of course this has been one of the coldest winters in 30 years for my area, so a normal winter might not be as expensive.

2 pics are just the growbeds, one is swiss chard and the other is strawberries. The strawberry plants have expanded, We started with 8.