Cold water tank to tropical

[rball@totalise.co.uk]

Hello

I currently have a 5.7 US gallon tank with in built in filter, it is a 'Fish R Fun' hexagonal tank.
In it I have two small goldfish, and yes I am aware that this tank will be too small for them when they grow, which I intend to rehouse in a friends pond when they get too big for the tank.
My first question is what do I need to know about putting them into a pond, I think they are comet goldfish, can they just go straight into a pond?
Secondly when I rehouse the goldfish I want to put a heater in the tank and put tropical fish in it as I will be able to have more fish in there then. Assuming the tank has gone through it's cycle and ammonia and nitrite levels are low can I just take out the goldfish, put a heater in and when it has got up to temp put a few tropical fish in?
Or do I need to completely clean the tank and start afresh.

Many thanks

 

[The-Wolf]

Personally, i'd clean the tank and start afresh. Goldfish can carry some diseases that are deadly to tropical fish.

As for adding the comets to a pond, it is the same as adding fish to an aquarium.
Put in a plastic bag tie the end and float in the pond for around 30mins to equalise the water temperature, then slowly let the fish swim out of the bag.
HTH

 

[Inchworm]

Hi rball@totalise.co.uk

Welcome to the forum.

I agree with danio2004's method of making the change from tank to pond, but want to caution you that this is only good if the temperature of the tank is close to that of the pond. If it is more than a few degrees different, it would be best to get them used to the temperature more slowly.

Another thing to consider is that the water chemistry might be different. It might be good to check the pH to avoid a sudden shock. If this is the case, fish can be helped to adapt by adding some of the pond water to the tank a little at a time over several days or longer depending on the amount of difference.

If you are able to make the switch without adding pond water, I think your tank is probably safe to use for tropicals. I've had success doing the same thing and it is a shame to waste all those beneficial bacteria. If the goldfish appear healthy, I would take a chance rather than subject new fish to the cycling process.

 

[rball@totalise.co.uk]

Many thanks for that.
Not too sure when they will be too big for the tank, but hopefully when they do they can happily move into a pond.
Cheers