Backyard Aquaponics
A place to discuss aquaponics

Hi,

I'm obviously new posting here. Just need some help if there are any kind informative people out there, which from reading this forum there seems to be an excess of

BACKGROUD: I work in the hydroponics industry installing commercial grade systems in large greenhouses providing tomatoes, capsicums and cucumbers to Australian supermarkets.

I have an awesome NFT Hydroponic system at home pumping out heaps of tomatoes, some herbs and lettuce. I am new to Aquaponics but love the idea of it and a good challenge. It has greatly facinated me since i found out about it.

So i went to bunnings, got a 160L container, 8 baramundi fingerlings, a pond pump, a heater, and a 3m gutter in which to plant my seedlings in perlite pots.

Results so far: Plants are great and 4 fish dead. Root cause i believe is ammonia levels getting to high as i got a test kit and watched them rise. I have a bio-active additive called Aquarium Rapid Start, containing Nitrosomonas, Nitrobacter, Nitrosospira and Bacillus Species which i hoped would help control this but I believe my 8 seedlings are not big enough to provide a proper filter.

ANYWAY: I changed the water after the apparent deaths due to conditions. I believe my seedlings will be be big enough to handle this but just wanted to check if there is any big flaw in my overall setup.

Thanks a heap for any replies or even if you just took to the time to read this

Cheers

Al


PS attached is a beautiful paint diagram of my system lol

Welcome to the forum.

Always good to have more people here with a hydro background.

First off, you got barra fingerlings from bunnings? I've been going to the wrong bunnings!

You'll need more of a filter than just the roots from the plants, it's not enough, and the poop will clog up all the root system and not let water through.

Have a look through Ryan's backyard system, his filters are quite simple, but work extremely well:
viewtopic.php?f=18&t=8754&hilit=ryan

You might find there are easier species to grow in SA. Things like trout grow great over winter, and for something year round without heating, look at Murray Cod & Silver Perch.

Thanks Columnmn,

That's very useful info. Thanks for the link as well, although looking at that just blows my mind for now

Do you think my system might work better if i filled my gutter with compacted clay rather than just leaving it empty (like my hydro setup)?

Also i noticed a buildup of fish droppings in the base of my container, whats the best way to deal with this? I assume if you have enough plants with sufficient roots and perhaps the compacted clay as mentioned above, these solids should be mixed up and then sucked through the pump into the grow bed? Maybe i could also get some worms in there?

Also is it worth having anything at the bottom of my container? In this case i am using a flat bottom oblong container.

Haven't you ever been down the Aquaponics isle in Bunnings

Cheers

Al

I haven't used any NFT, so some others around here might be able to answer the questions better.

But usually, it's 20-25 fish per 500L of media (be that gravel/compacted clay, etc). But that's wet gravel, it gets more complicated the more you look into it, but that's an easy thing mark to follow. I believe NFT is just a thin layer of water that runs along the length of the pipe? So the water isn't over the whole lot of gravel. So less room for bacteria to grow.

Have a look through here:
http://www.backyardaquaponics.com/guide ... -stocking/

Another thing to remember is that you want to try and turn over the entire volume of the fish tank twice every hour.

Ryan's filter isn't that difficult, just water coming from underneath into a garbage bin, passing through some plastic balls (can be anything, (milk bottle lids for example), and then passing through some shade cloth, with a bubbler at the bottom.

However, I'd recommend looking into starting a media based bed. It's far easier to begin with. Far less things to go wrong. You'll struggle to keep temps down over our Adelaide summers with the NFT, and high temps will cook the fishies.

At the top of this page there is the IBC of aquaponics: http://ibcofaquaponics.com/

It's got all the information you'd need in there.

Another thing I didn't see in your description, do you have an air pump?

Sorry, I know this is confusing compared to what you're used to with Hydro. But it's worth it. I took out 7kg of tomatoes from by system on the weekend, and it's amazing to look at that and realise it all came from fish poop.

Thanks for your help!!! A few answers to your questions.

The water drop out of my gutter is about 0.5m which provides a lot of aeration in my 160L container.

The water pump would easily turn over the water about 5-6 times every hour.


I was wondering how the solids at the bottom of the tank might be biodegraded? They don't seem to get sucked up into my pump, so not sure how the cloth/bucket filter would help?

I'm just using the following pump.

http://www.bunnings.com.au/aquapro-ap750lv-pond-pump-kit_p2810056

You'll have some of the poop being sucked up into the pump, but unless you've got a proper aquaculture, bottom draining, sloped tank; you'll never get all the crap out of the tank. It'll settle.

I usually have a go at it every few weeks with a big broom. Gets it all off the bottom of the tank.

The cloth/bucket filter is a bio-filter. It's where the bacteria grow that convert the ammonia to nitrites/nitrates. The bacteria grow on pretty much any surface, the more surface area, the more bacteria can take over. And the balls Ryan used (very cheap on ebay), and the shade cloth has quite a large surface area, so plenty of room for bacteria to convert the fish waste.

You don't want the fish solids going into the NTF, they'll clog up your roots and give you stunted growth. The bio filter catches all the fish solids, and as they break down in the filter, they'll be converted into nitrites/nitrates, and release their nutrients into the system.

The reason I recommended the media bed is that you don't need to worry about the majority of that, as long as you've got a good stocking rate, all the poop goes right into the media bed, and you plant right into there. You grow your plants in the filter itself.

If you're close to Elizabeth, I'm happy to give you a walk around of my system, show you the Bell syphon/dwc in action, and different things like that. And I can quiz you on the finer points of commercial hydro production

Fish keeping without a bio filter.
Nft without a filter.
Perlite in ap.

Hmmmmm.

Me thinks More research required.

I pretty much agree with everything Column has said except for...



Aquaculture tanks often don't have sloped bottoms and when they do it is so they can be easily fully drained of water. What allows AQ tanks to efficiently remove solids is the circular current in the tank and a drain in the center of the tank floor to collect the solids that are concentrated there by the currents in the tank.

More research is needed and as Column advised the IBC of aquaponics would be a good start.

Look up Biofiltration.

Biofiltration is a prerequisite for the nitrogen cycle.

lucky bioaquafarm isn't here anymore.

I bow to your superior knowledge, I've never had a proper aquaculture tank, I was just thinking that'd be the best way for it to drain. I'm making one soon, so I was planning on it that way. (In ground, I don't want a crazy lap from my labrador taking out a pipe and draining it all.).

It's an easy mistake to jump into it for Medium when he's from a hydro background. Just swapping the fish with the hydro chemicals. Sadly, the remaining fish won't be happy

If he gets some sort of bio filter going soon, they might survive. Just stop feeding them for now (and salt to help with the nitrite poisoning?).

Thanks for your help

I've changed the water so should be ok for a few days. Remaining fish seem happy.

I've built my bio filter now from the links, just need the media.

Is there anything I can use from Bunnings or somewhere else easy to get? No fish shop seems to know what bio balls are?

Cheers

Al

I haven't seen the balls in a fish shop. I haven't really looked though.

http://www.ebay.com.au/itm/50x-Aquarium ... d35&_uhb=1

But shade cloth is in bunnings, buy a few meters of it.

You also need to think about putting a bubbler at the bottom of the filter, otherwise you'll get anaerobic conditions developing in the filter, which doesn't lead to good things. And the plants will need a certain amount of oxygen (which is also being taken from the bacteria and the fish).

I used bird netting in a biofilter, was on special at the B.

Perlite actually works great in AP

Thanks for the shade cloth idea.

If I fed the bio filter from the top (instead of from the bottom) it would cause aeration. What do you think?