Backyard Aquaponics
A place to discuss aquaponics

I' had the ICB filled for the last week and a half and just been cycling the water through. Tested the water this afternoon and the readings were:

Ph 7.6
Ammonia 0
Nitrite 0
Nitrate 0

I'm using the API freshwater master kit.

How are these numbers? Am I ready to introduce some fish?

Yes, and no... I doubt that you're actually cycled within a week and a half.... did you add any ammonia source???

You can cycle with fish... but you need to be pedantic about testing... and feed levels... and responses...

Did you add any source of ammonia? Charlie Carp? Humonia (pee)? If an ammonia source has never been added to the system, then it wont have cycled.

For 1000L of water in an IBC, I'd be adding 30-40mL of Charlie Carp which will give an ammonia reading of about 1.5-2.0ppm At what I am guessing to be Qld water temps, it will take about a fortnight(?) for this to reduce to zero ammonia, zero nitrites, with any nitrates being used by any plants you will add/have added. (Personally, I don't like cycling with fish, but you could add some sacrificial goldies or something to kick start process in lieu of fishless cycling.)


Scott

No, I did't add any ammonia source.

What do you mean by you doubt it's actually cycled in that time? Is a cycle one full turnover of the water in the ICB?

What are ideal readings to be aiming for?

Edit: no fish or plants in the system.

"Cycled" is a term for completing a lap of the "nitrogen cycle" as graphically displayed in the IBC of AP. Ammonia is converted into nitrites, then nitrites into nitrates. When your system starts lets assume there are minimal naturally occurring beneficial bacteria in the system, so we need to feed them with a little bit ammonia in the first place. This will be converted into nitrites and then a second naturally occurring bacteria will convert this into nitrates which are readily used by your plants.

When any added ammonia is completely used, and any generated nitrites are completely used then your system might be considered cycled. Personally, I add a time factor; when all the ammonia and nitrites can bve converted to nitrates within 24 hours then I call this "fully cycled"

Read more in the free "IBC of AP" http://www.backyardaquaponics.com/Travis/IBCofAquaponics1.pdf

Water Turnover: a general rule of thumb is that you want to pass all of your water through the GB once per hour, so if you're only completing a water "cycle" in a week, then you're going to need a much bigger pump!

If you're going to run your system as continuous flood then you need about 600LPH pump (discounting the effect of any head losses and assuming you chopped a single IBC to build your system), or if you're going to use a timed flood and drain, then you're going to need something in the vicinity of 2000-3000LPH for a 15on/45off cycle (although I have seen smaller pumps effectively used in IBC systems)

Again, there's lots of information in the IBC of AP book.


Scott

It is a good idea to get the plants established in the grow beds before you introduce the fish. Small plants don't need a lot of nitrate, so you could end up with too much nitrate (from fish) that the plants can't absorb. Start some seedlings, and use a foliar spray (eg seasol) if you want to give them nutrients without adding it to the FT as part of your cycling. That way, when you introduce the fish the plants are waiting to absorb any nitrates created from the fish waste.

Thanks to you all taking the time to reply. I do actually have a printout of the BYAP book, but I'm not a book-learning person IYKWIM? It just doesn't sink in for me. Sorry, will try to get more out of the book and forums before posting next time :-)

Don't be sorry! This thread answered about a dozen different questions I've had! lol