Aquaponics 101 – The Ammonia Wars

Death is Natures way of saying that you are no longer needed in the Eco-system.



I just knew that something was going to be wrong in the system when I woke up on Saturday morning, and once again, my instincts were proved right, Six dead Tilapia floating on the surface greeted me when I checked on the tunnel. These I scooped out, and all showed signs of lack of oxygen. I immediately switched on the emergency oxygen and decided on a course of action. In a situation like this there are numerous remedies, and combinations of them yield the best results.

Firstly, determine how bad the situation is. This involves a water test. This is what the result looked like.


Ammonia 2+
Nitrites 0.5+
Nitrates 75

I also tested the pH (6.5, too low) and the Dissolved Oxygen (very low).

The course of action, because the new grow beds are going to take a while to start working, are as follows;

Stop feeding immediately for at least 4 days. This will reduce the Ammonia secreted by the fish when they eat.

Clean the tank. This will take out any rotting faeces and uneaten food (and dead fish?) that may be accumulating at the bottom the tank.

Water change. This will dilute the dangerous levels of Ammonia and Nitrites.

Reduce fish levels. Nature helps here by killing some off. Fortunately I have a farm dam now, so we can just move the excess fish across. The fish levels are a problem because I was over-stocked to start with, and with the fish growing so rapidly, they consume more food, excrete more Ammonia, and use more oxygen.

One gets to know the fish by feeding them daily and observing them. This is the advantage of hand feeding as opposed to automatic feeders. Looking at these fish, I just know that they are not happy. Look how they are crowding on the surface, almost as if trying to get out of this toxic water.


We lost probably another 15-20 over Saturday and Sunday, but I did manage to save a few by applying oxygen directly over their gills.


Sunday saw us (the child bride, brat deluxe and me) cleaning the pond and replacing with new water and moving about 150 Tilapia out to the farm dam, where they seemed very happy with their new “super-sized” pond. The fingerlings which I am holding in this dam seemed very interested in these new arrivals, and before long they were all swimming around together.

The problem that I will have now, is that as these plain Tilapia fingerlings mature they will mate with my red males that I have just introduced, but because the red variety is very recessive, the fry will probably all be plain. The only way to get some red fingerlings out of this dam now, would be to introduce some red female brood fish as a soon as possible (ie before the fingerlings mature and before Winter), which I think I’ll do in a week or two.

All in all, a very eventful weekend.

Cheers for now



One thought on “Aquaponics 101 – The Ammonia Wars”

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s