Zebra fish can really jump!

[NotTheMrMenAgain]

Hello. We got a new 26 litre tank recently and our 4 zebra fish have been in for almost 3 weeks now. The plan is to introduce a few mountain minnows later and leave it at that. Everything has gone well so far, the zebra fish seem happy (haven't died), are eating well etc.

They chase each other around quite a bit, but I think that's normal for zebra fish. One particular fish did seem to be a bit of a bully and would chase the others in a more aggressive way, but seems to have settled down lately.
However, this evening my DH called that he could only see 3 fish in the tank - we found the 4th under the sofa! Heaven knows how long it had been there - my DD had a glass of water so I scooped it up in a panic and dropped it in the glass. It was a bit fluffy but came round and luckily seems non the worse for it's leap of (almost) death.
We looked on-line for some guidance and eventually found a site that said zebra fish are well known for their jumping/escapologist habits. I did not know this and bought a fancy open top tank with a water feature thing over it, so I can't put a cover on. Doh! We got the fish and tank from a respected aquatics place and they told us exactly what to do re: set up, but nobody mentioned the jumping!
I've covered most of the top of the tank with cling film, as a temporary measure. Please can anyone tell me if the jumping behaviour indicates that the fish is unhappy/stressed, or is it just something they are prone to do every so often?

I am worried that jumper-fish was driven to it by chasing from bully-fish. Jumper is back in the tank now and I don't want it to feel stressed. Do you think I should take Bully out of the tank - this would be tricky as they are blooming fast and all sort of look the same.

I read somewhere that putting in more zebras can tone down aggressive behaviour - I could put more in but don't want to end up simply with more jumpy fish.

Does everyone agree that we should buy a new tank with a lid for the zebra fish and put something much less frisky in the open tank?

Everyone says that having an aquarium is relaxing! When will we feel relaxed? I just heard a strange little sound that may have been a zebra fish bouncing back from a cling film force field.

Hello,

I can see why your fish may have jumped. I'm afraid the aquatic place hasn't given you very good advice!

For a start, your tank is far too small. Unfortunately there are a lot of tanks on the market that are too small for any fish at all, and there's nothing to stop shops and manufacturers selling them. The minimum size I would say for any fish (and the RSPCA agrees) is 45 litres. This would limit you to a very few species. Zebra danios are very zippy, active fish so need a larger tank, even though they are not very big. I'd say 80 litres at least for a shoal.

Another problem is the number of fish you have. 6 is the minimum number really for a shoal. In smaller numbers, aggression is not spread evenly amongst the shoal so you'll often see bullying and end up with maybe just two fish.

The limited space can also cause aggression problems because the fish are so packed in.

If you only got the tank and fish 3 weeks ago then it won't be cycled, so the water quality may not be up to scratch- this can also cause jumping. Have you got a water testing kit? Did the shop tell you anything about the nitrogen cycle at all? It normally takes about 4-6 weeks before a tank is ready for fish, if you add them before this then you'll need to do extra water changes (especially since the tank is small). Have a look here for more info.

Buying a new tank for the zebras is a great idea- if you went for 90 litres+ you could also have the minnows but it would be better for the fish if you just had a larger shoal of the zebras. A shoal of 10 would be ace, they would show more natural behaviour and be much happier.

Sadly the open-topped tank isn't suitable for fish. You may be able to return it under the sales of goods act, there was a thread about this the other day with lots of info.

Sorry for all the bad news :( and sorry that the shop has given you such shit advice. I hope you manage to get it all sorted. Let me know if you need any more help!

Here is the thread about returning unsuitable tanks.

Eau, thank you for all of the info! I am not v impressed with the shop now and feel like a bit of a mug really. In hindsight I should have done proper research prior to buying anything, but I was totally confident re: the advice I was given.

It seems I bought my fish from the fishy version of puppy farm - cram them in and tell the customer anything to make a sale and make it all sound very easy! I think all shops and garden centres I've seen operate on similar lines to be honest.
On the bright side, I think my fish are better of with us than at the shop (loads in a small tank) and we'll be looking into getting them a more suitable tank ASAP.

Yes, pretty much all shops are like that, some are worse than others. Sadly there's more money to be made by keeping fish badly :( who the hell would even bother getting a goldfish if they knew how much time and space (not to mention money) they needed? It's cheaper to keep replacing the fish than to buy it a decent tank.

Anyway, you're not a mug, you did what any reasonable person would do and expected the people in the shop to know what they are on about- unfortunately most don't, or are told to sell things a certain way.

Good luck getting a new tank- freecycle, free ads, ebay and gumtree are all packed full of bargains so you should be able to get something cheap and easily.