Strange cardinal tetra behaviour

I am a new aquarium owner. I have a 125 litre fish tank that I have had set up since the beginning of May. I have only had fish in it since Saturday though.

On saturday day I went and bought 5 Serpea tetra, 6 Cardinal tetra and a male Siamese fighter all at the recommendation of the shop keeper. Although I think one of the cardinals may be a neon tetra. The two fish I really wanted was the cardinals and the betta. I came home from work on Monday to see my betta and cardinals hiding in the plants. When they did come out I saw chunks had been taken out all of their fins to the point on of my cardinals struggles to swim now.

I took the Serpea tetra out and got 10 silver tip tetra and added them in on Monday. All my fish were happy and swimming around fine. Came home today though to not find any cardinals. My betta is swimming around fine and the silver tips are chasing each other round like crazy! Every time the silver tips go near the plants that the cardinals are hiding in the cardinals retreat further in...

I fed them today and the silver tips ate most of the food and when the cardinals came out to get some food and a silver tip came near it left the food and swam away... I can't check the cardinal tails as they already were damaged and they won't come out of hiding.

are my silver tips bullying the cardinals? Do I need to buy more cardinals?







my cardinals are hiding down the back by the filter

 

This is my experience with Neon and Cardinal Tetras.

They are fabulous fish and I can't see myself being without them.

However, they have their drawbacks.

They are easily suppressed by more boisterous species so I choose their tank mates very carefully.

You have two shoals competing for resources of space and food.

Also, I have observed that larger species can stress them even when the larger species pose no real threat. I think this may be because these small tetras are a food item for larger species in the wild. Stress can kill.

My Neons are with Glass Catfish which are so peaceful that I never saw one chase a Neon.

If I were you I'd keep either the Cardinals or the Silver Tips not both. If keeping the Cardinals either keep a spectacular large group of them or choose tank mates carefully.

 

Hahaha I had this discussion about Silvertips yesterday. A friend brought them back caise of this. I have them as only not-bottomdweller in a tank. got them from someone for the same reason. They are great but these guys speak their own "language" that is often misunderstood by humans and other fishspecies. They'll even chase each other. This is completely normal and their "way of life" but making them not a great communityfish.
This is not gonna change I am afraid. Sorry !

 

Oh right I have read that they chase each other before mating and have now noticed that some of them are looking really fat and hovering above the leaves of my plant? Might they be laying eggs? Would adding more cardinals than silver tips make the cardinals feel more comfortable around them??

 

They are chasing each other constantly hahaha.
That you could try !