Backyard Aquaponics
A place to discuss aquaponics

For a rounder shaped tank base - ie pond, I added sand and then a bag of beans from an old bean bag as insulation. It rounded the bottom out nicely but if you don't want it rounding use sheets of it instead.

Who decides these things?

I understand the preference of chickens or quail, for example, for small social groups, but fish quite often get around in very large schools in very close quarters. In fact, they seem to find comfort in security in numbers.

We don't know what fish think.....or even if they do....about such things.

While I don't disagree with the need to heed genuine animal welfare considerations, I'm not into anthropomorphism......."the attribution of human motivation, characteristics, or behavior to inanimate objects, animals, or natural phenomena.”

Anthropomorphism.....more commonly called the "Bambi Syndrome"...... is "a pervasive element of literature, employed by many different authors, of many different genres, to imply many different things, usually some sort of social criticism." In short, it leads to an entirely unrealistic view of animals (particularly those that are important food sources) to the point where farmers are inappropriately restricted.

Let's see if that doesn't let the cat amongst the pigeons.

Hahaha!

My cat gets angry, no argument there. Ears pinned back, growl emerges, walks up all stiff and jaunty, smacks me, then walks off. This when I tease her.

6 kilos per 100 litres denotes about as high as you can stock for O2 demand Gary. Definately for experts, 2 degrees out and everything can die.

Good AA......I thought there was an entirely practical explanation in there somewhere.

I thought I'd read somewhere (and I think Wilson Lennard wrote it) that up to 100kg of fish per 1000 litres of water was possible. That may have been a commercial recirculating aquaculture system......and they really thrash the air into those things.

I think you are right GD, 100kg per 1000 litres is about what commercial aquaculture farmers stock at. And not only do they pump in the oxygen, they pump out the water too!!

The system slowly progresses - appreciate the input to date! Whilst waiting on the grow bed, I have started to plumb the system in. Also placed the tank on 5mm board, which will act as insulation.

Pics show the piping and a value for regulating the water to the proposed grow bed. Also installed is a tap which can connect to a hose to drain the system (when required) and also run water back to the tank to assist with aeration / requlate flow.

More pics to follow once the grow bed arrive............ really hope it arrives soon as I am off overseas for a couple of weeks and want to get the system cycling before taking off......

Based on feedback plan 20-30 fish for the 1365L set up (fingerlings) to start with.... also do not plan to use an air blower / 'aquarium' pump - welcome members thoughts on the yes / no of employing separate aeration in a 1365L tank......

Marcus, you have heaps of surface area there, I would say IMHO, you wouldn't need extra airation for 30 fish. See what others say though

Your plumbing looks really neat. Good job

Have you considered putting a non return valve and a barrel union above your pump. NRV will add life span and for around $20 they're cheap insurance.

Now that is a tidy job! good work there.
I agree on the DO... should not be a problem for you at all!

Looking good!

GD, the figures 6kg per 100L is an idea of the maximum stocking density for a flood and drain aquaponic system that has a growbed to fish tank ratio of 2:1.. This is based on trials in the US over a number of years..

Marcus, great work, that is very neat plumbing.. Does anyone know about those building blocks that you have the pump sitting on? I've used a couple of clay house bricks in my system and they seem ok, are those large ones going to be ok in fish water? I only mention this because I thought about using a reconstituted limestone block in one of my tanks and a friend warned me that perhaps I shouldn't.....

General consesis cone is a cone sand bed, and 6kg/100ltrs water people should be canned to see what its like!!!
Must be living on the edge.

I recon a lime stone block would be a good choice as it would provide a source of KH buffer, and in a system of that size its size is proportional.

Garry Donaldson mentioned something about "additives" used in concrete, as long as the reconstituted limestone block didn't have any "funny stuff" in it i reckon it would be sweet.

Marcus, that's a nice tank. I agree with other posts about plenty of surface exchange. My immediate question in looking at it is why not put the pump on the tank bottom? How do you plan on getting the solids out?

EB, thanks for clearing that up, will use AA's figures and that will leave a good sized safety margin.

Appreciate the feedback.

In the UK we call the bricks "breeze blocks", I believe they are made of ash/concrete - and are generally used as the inner brick in house construction. Assume it will be OK for tank????

I am also assuming the tank will be too deep for the float to work correctly, hence the block to give height - but I could be proven wrong - if so, I will house it on the base.

How do I plan to get the sluge out? I plan to make a siphon and link it to the outer drain - still work in progress.

Just heard that the grow beds are being despatched tomorrow - hooray