Shy fish?

[Alex280]

Is it possible for a fish to be shy? My variated platy lives in a 30l biorb with another platy, a zebra Danio and a black moor. It spends most of its time hiding either in the central coral or in the substrate at the bottom. The other fish are swimming about quite happily, so I don' think it's an issue with water quality or anything. Is she just shy or are platies known for burrowing?
Any answers would be gratefully received.

 

[Essjay]

I am sorry to say that none of your fish are suitable for a 30 litre litre tank.

Fancy goldfish, and the black moor is a goldfish variety, need at least 100 litres just for one fish. They grow a lot bigger than most people think. They also need more filtration than other fish. http://www.fishforums.net/threads/goldfish-for-beginners.417799/

Platies need a tank at least 2 feet long. What is the sex of the other platy? If it is male, it is probably pestering the 'shy' female. Livebearer males are like this, which is why they should always be kept with at least 2 females for every male. But not in a 30 litre tank.

Finally the danio. There are a couple of things to say here. Firstly, they are shoaling fish so they need to be in a group of at least 6 of the same species. They have evolved to live in groups of hundred or even thousands, and having just one is very stressful for a fish that needs to be in a group. The second thing is that these may be small fish but they are very fast swimmers. Owners who have them in 4 foot/120 cm long tanks say they can cross from one side to another in under a second. Because of this they need to be in tanks at least 100cm long, with longer being better.



How long have you had the tank?
What are your readings for ammonia, nitrite and nitrate? With so many fish in 30 litres, and one of them a messy fish, the nitrate is quite likely to be very high which will stress the fish.
What temperature is the tank? Black moors are cold water fish, zebra danios are temperate, needing a temp of 18 to 22 deg C while variatus platies need 20 to 26 deg C. If you don't have a heater, the 'shy' platy might be too cold.
How hard is your tap water? Platies are hard water fish and won't do well in soft water. You should be able to find your tap water hardness somewhere on your water provider's website - you ned the number and the unit as they could use any one of half a dozen units.
How often do you do water changes, and how much do you change?
Are there any live plants in the tank?

The more info you can give, the better we can advise.