Urgent Advice Needed On My Tank Please!

Hi All,
I have recently set up a 55 litre tropical tank.
I cycled it using 2 danios & filter media from my other tanks in preparation for having malawi cichlids.

I tested the water 2 days ago & all readings were o.k Ammonia 0, Nitrite 0, Nitrate 10. I added the rocks prior to putting the cichlids in & also buffered the PH to 8.2 for them.

I added 3 medium sized cichlids & 1 puffer to the tank yesterday afternoon.

Tonight I noticed that the puffer is just lying under a rock, one of the cichlids was hiding inside a cave and the other two were swimming around o.k. So i decided to test the water as I thought something wasn't right.

Test results showed Ammonia 0.5, Nitrite 0, Nitrate 20.....Please could someone advice on whats happened in such a short period of time, suddenly got ammonia but Nitrate has also increased.

What has gone wrong or this o.k???

Added to many fish to soon and the tanks gone into a mini cycle.
Water changes and increase aeration.
What's the name of the cichlids and puffer.
The tanks sounds overstocked to me.

Wilder said:

Added to many fish to soon and the tanks gone into a mini cycle.
Water changes and increase aeration.
What's the name of the cichlids and puffer.
The tanks sounds overstocked to me.

Click to expand...

I don't know the exact name of the cichlids. When I bought them from the shop yesterday they were sold as assorted malawi cichlids (Small,medium & large). I bought 3 medium ones. I don't know about the puffer, its got green & yellow spots if that means anything.

So should I do a water change immediately?

Could it be anything to do with my filter.....it does manage 550L/PHour though?

I think your tanks overstocked.
Always research the fish before you buy as some lfs will tell you anything to make a sale.
I would do a water change now and increase aeration.
Going to get someone to take a look at your stocking.

Most likely, as Wilder mentioned, the tank is in a mini-cycle. You added 4 fish to a tank that was cycled with 2 fish. That doubles the bio-load but the cichlids are probably bigger waste producers than the danios, thus meaning you could have tripled or quadrupled the bio-load. Nitrifying bacteria ae slow to reproduce, doubling in approximately 24 hours, so the bacteria should catchup in 2 to 4 days.

As mentioned, do water changes as needed to lower the levels. The test kits we use measure total ammonia which is ammonia (toxic) + ammonium (non-toxic). As pH levels rise, so does the amount of toxic ammonia making the ammonia reading of .5 in your 8.2 pH water much more harmful than it would be in water with a pH of say 7.0.

I have never kept cichlids or puffers but would think that you you are overstocked for a 14-15 gallon tank depending on what type cichlids they are. It has nothing to do with inches per gallon but a matter of aggresion and territories. Also, I think puffers need brackish water and should be in a species only tank. You need to find out exactly what type cichlids you have (photos would help someone ID them for you) so it can be decided if you have compatibility and over stocking issues.

Just managed to get some photos of my 3 malawi cichlids....hope this helps

This is the third malawi cichlid.....

It looks like 2 Metriaclima estherae one male and one female. And one male Melanochromis auratus. You are way overstocked and your filter can't handle the bio-load as the other two have mentioned. Do some water changes right away until the ammonia is gone. Then, take back the cichlids or get a bigger tank.

I would phone the lfs and see if they would take the fish back.
Research fish before you buy as not all lfs can be trusted.