Backyard Aquaponics
A place to discuss aquaponics

Hi All

I have been a long-time lurker on the forum with a very long-term interest in aquaponics. However I have just decided to take the plunge, so to speak, and have build my first AP system.

The system is build from IBC's and consists of a 900L fish tank, 900L sump, 200L DWC raft tank, and 2 x 400L gravel filled grow beds. I will be adding an additional 800L of gravel grow beds in the next couple of weeks. Aeration is provided by lots of splashing water, and a largish air pump (putting out ~2,000L per hour).

The system has been running for about 2 weeks without fish, and today I added rainbow trout fingerlings to the tank. The water is quite turbid, due to not washing the gravel, but I think that the trout should be OK. Well I am hoping!!!

However I do have one question that I'd like to throw out to the board. I have been testing the water daily for the last week during which I was adding a very small amount of urea to give the bacteria a leg up. I have also added a couple of hundred litres of pond water from a koi pond elsewhere on the property.

My question is that I have been getting some 'odd' results with the tests. I originally had a rising ammonia level, up to 3ppm, along with some nitrates. The ammonia has begun to drop, however I haven't had any nitrites show up in the system at all. Does this seem a little odd?

My heart tells me that even though the system is young it has cycled (probably due to the injection of bacteria from the pond) but my head tells me that it is way too early. What's your thought?

I have attached a picture version of my spreadsheet with the parameters recorded. The TAN is a calculated field based on pH, Temperature and total ammonia measured by the test kit (API Freshwater)

Cheers
Shane

Hello and welcome to the forum.

I would say that the bacteria which converts nitrIte to nitrAte is coping with the amount of ammonia which is getting converted (to nitrIte).

You have also broken the unofficial rule of this forum - you need to post pics of your system!

Ah! I don't have any stills currently but do have a yideo floating around (http://www.youtube.com/watch?v=XvnS1wBXCDM). I'll pull together some stills after I make a few changes this weekend.

That's for the toughts re: cycling. I was kind of thinking the same thing though it'll be interesting to see how they cope with the new fish load.

Cheers
Shane

In your video you mention you are going to put 80 trout in your fish tank. My feeling is your tank is a little small for that many trout. You certainly have he filtration (when you add another 2 beds).

System looks good though.

Just lightly feed when you get the trout to check how the bacteria copes with the increased load.

I am with arbe 80 fish is way to many for an ibc I wouldent go over 40 and to be safe for the first run 30 would be better
For 40 trout in an ibc you will need a good air pump

I have done 80 trout in an ibc, but you need a heap of water circulation. It definitely won't work for your system.

You'll get them to 3 or 400 grams and loose the lot overnight.

Hi All

I'll review the plans... :-) Outbackozzie, what makes you say that they'll get to 3-400g and then lose the lot? Always interested in an alternative point of view.

Cheers
Shane

Water quality. You'll excedd the maximum bioload for your system.

I was running that many fish in an IBC hooked up to an 8000 litre tank, with a 4000 lph pump.

OK... see where you are coming from.

Filtration should be OK... the new bed coming online in about 3 weeks will have a gravel volume of about 1500L (in addition to the 800L currently and the 200L DWC), and another unit like this will be brought online a couple of months after that. However I'll need to consider the water quantity.

Good advice, I'll do some thinking.

But there are supposed experts here in Australia who actively recommend putting 100 fish in your 1000L tank...

It's a bit like shooting yourself in the foot before running a marathon, and certainly not good for people new to AP.

Good for fingerling sellers though

I appreciate the candor, and the rethink has begun. I still need more time to work out the details but I think the gist is that a second fish tank will be brought online in a next couple of months and the fish split between the two (can't do much about their arrival after they have arrived).A second tank was 'sort of' planned anyhow so it's not too much of an imposition to set it up.

Of course that means more grow beds but I can live with that.

The only major change will be needing to incorporate an indexing valve. Anyone know an Australian supplier? I have only found an American supplier however with the current exchange rate that might not be a bad thing at all!

Cheers
Shane

Calling Rupe. Where are you?

Austbodhi... any "amercian" supplier... should have directed you straight back to me....

Contact me via the website in my signature...

Hi Rupert

Have dropped you a line. Thanks for pointing me in the right direction.

Cheers
Shane