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Cycling Day 5

After waiting 2 more days, the ammonia test results didn't change. The pellets are clustered on the sand in one spot between the rocks:

They look fuzzy: they are definitely decaying but very slowly.

At this point, we have a few options:

  • Wait and keep testing for ammonia until we reach a higher concentration.

  • Remove the decaying pellets with a gravel vacuum and add different fish food instead, like another cube of brine shrimp or flakes to increase the ammonia concentration more quickly.

  • Increase the flow or adjust the return nozzles to break up the pellets in hopes that they decay faster.

  • Add bacteria now and let it start consuming the ammonia that exists in the tank. The decomposing pellets should keep adding ammonia to feed it.

I decided to go with the last option. I like that the pellets are staying in one location so I can keep an eye on their state.

Adding the Bacteria

Dr. Tim has a video with instructions if you'd like to watch it but the gist of it is:

  • Turn off the protein skimmer and UV sterilizer if you have one. They should be off already, since this was one of the rules we discussed before we started.

  • Remove filter socks. The bacteria in the bottle are grown on small particles and we don't want these to get stuck in the filter socks, we want them to colonize our rocks.

  • Shake the bottle and pour half of it in the tank.

  • Expect the water to get cloudy.

  • Don't clean the gravel or change water.

I'm going to do just that.

  • First, I'm going to remove the filter sock and place it in the tank. I still want all the decaying food that has been caught by it to stay in the water. I'm going to remove the fiber balls that are in the media basket and put them inside the filter sock for the same reason. It's OK if they stay inside the tank, we just don't want them to trap the bacteria in the overflow water.

  • Then, I'll take the bottle of bacteria out of the fridge, give it a good shake and pour half of it in the main section of the tank. You don't have to be very precise: you cannot add too much bacteria.

Moving the filter sock and fiber balls stirred up a lot of brine shrimp and the water did get a bit cloudy:

You can see the filter sock hanging inside the tank for now. The fiber balls are inside it. You can also see floating brine shrimp and the cloudiness from the bacteria's particles.

Experiment Progress

The Seachem Ammonia Alert badge I placed in the tank has changed colors slightly which means we're going in the right direction. It's worth mentioning that our API ammonia test results include both ammonium (NH4) and free ammonia (NH3) whereas the badge only measures the latter since it is the toxic one. The total concentration shown by the test results is expected to be higher than what the badge shows.


The food has not been decaying very quickly and there's still a lot left. This leads to me believe that there will still be a lot more ammonia generated as time goes on. Hopefully, the bacteria will begin reproducing and consuming it soon. If that's the case, we should see an increase in nitrite.

We'll wait another two days to see what happens.