Using Goldfish To Cycle New Tank

[Kiwi Clint]

hi all
My son and i currently have a small 40 litre tank with 3 goldfish in it. They have lived happily for 2 years. We have now decided to step it up and have purchased a 3 foot tank. Just been reading up on the whole cycling thing (which is all new to me!) what are your thoughts on using the gold fish, and placing the small tanks filter into the new big tank (along with the new tanks cannister filter) as a means to expediate the whole cycle thing....Dont want to kill the goldfish (thou they are hardy buggers, my 6 year old son hasnt managed to kill them!)but think this is a sound idea.
Appreciate your thoughts

 

[Warehouse]

Personally I would cycle the new tank without fish but use a nice chunk of your current filter media inside the new filter. That way the fishless cycle will be over much quicker than usual and you get a chance to work out the best way to make the tank look as it's cycling.

...and welcome to the forums .

 

[Jenste]

it is cruel to cycle the tank with the goldfish - - but another problem is that you have three goldfish in a massively inadequate tank. The reason they are "small" after this length of time is that they are now stunted. Unfortunately at the pet stores, there is no such thing as a "small" goldfish, merely young ones. even your 3 foot tank may not be enough gallons for the 3 of them but it is certainly better than your current situation.

in hopes of bettering their current state, I would do the fish in cycle but do massive water changes daily for the first 6-8 weeks until the new filter has been able to build a bacteria colony.


are they commons/comets (single tail goldfish) or fancy (double tail goldfish)?

for ONE common, you need 30 US gallons of water then an extra 10 gallons per additional goldfish.
for ONE fancy, you need 20 US gallons of water then an extra 10 gallons per goldfish.


Goldfish are large and messy, commons really work best in ponds. We usually do not encourage people with out massive tanks to keep them but there are a few on here who have devoted large systems to goldfish.

 

[anon02]

If you keep the same number of fish it should be fine, if you intend to set the smaller tank back up I would give it at least 6 weeks with both filters running in the big tank before removing the mature filter

EDIT
Either I or posters # 2 & 3 have misunderstood your question

 

[kporteo]

I would do a fishless cycle in your new tank but put some of your goldfish's filter in your new filter to give it a kick start, but, I also would put some of your new filter in your goldfish filter whilst that one is running too, that will supercharge the filter.

K

 

[Kiwi Clint]

hey thanks for the replies !
wow, there i was thinking 3 goldfish (they are fancy) would be okay in the 40 litre (10 gallon) tank... They have lived happily for a couple of years in there...I now officially feel bad that i have crowded them.
Dont want to be cruel to them, so will leave them out of the cycling process of the new tank, but will put some of their filter media into the new tanks filter.
appreciate the quick answers....and as a newbie to this whole tropical tank thing, appreciate any and all advice !
cheers

 

[anon02]

Do you intend to close the smaller tank down ?

 

[Kiwi Clint]

Do you intend to close the smaller tank down ?

yeah i do, trying to find a home for the goldfish, and am starting a tropical collection in the big tank....just in the process of understanding what goes with what etc etc... My six year old is determined to have some harliquin rasborras and some neons in the big tank, but i would also like some bigger fish, know any that wont munch on the neons and rasborras?

 

[Kiwi Clint]

Personally I would cycle the new tank without fish but use a nice chunk of your current filter media inside the new filter. That way the fishless cycle will be over much quicker than usual and you get a chance to work out the best way to make the tank look as it's cycling.

...and welcome to the forums .

thanks for the welcome!...i have many questions.......have gone from "put fish in water and feed"knowledge level to "bloody hell"level in 10 minutes flat from reading these forums...all sounds good though and have just learnt that fish are like any other pet....care and attention required

 

[anon02]

Do you intend to close the smaller tank down ?

yeah i do, trying to find a home for the goldfish, and am starting a tropical collection in the big tank....just in the process of understanding what goes with what etc etc... My six year old is determined to have some harliquin rasborras and some neons in the big tank, but i would also like some bigger fish, know any that wont munch on the neons and rasborras?

In that case there will be no need to cycle the bigger tank, just leave both filters running

If you can plan it so that the goldfish are rehomed on the day that you get your new tropicals you could pop the goldfish back into their old tank with fresh conditioned water (they`ll be ok for an hour or so) while you change half the water in the big tank with conditioned water warm enough to bring that tank up to tropical temperature

The rasbora should be ok but the neons are better in a mature tank. Most fish will eat any smaller fish that will fit in their mouth so you need to research which species you can keep together

 

[Kiwi Clint]

Do you intend to close the smaller tank down ?

yeah i do, trying to find a home for the goldfish, and am starting a tropical collection in the big tank....just in the process of understanding what goes with what etc etc... My six year old is determined to have some harliquin rasborras and some neons in the big tank, but i would also like some bigger fish, know any that wont munch on the neons and rasborras?

In that case there will be no need to cycle the bigger tank, just leave both filters running

If you can plan it so that the goldfish are rehomed on the day that you get your new tropicals you could pop the goldfish back into their old tank with fresh conditioned water (they`ll be ok for an hour or so) while you change half the water in the big tank with conditioned water warm enough to bring that tank up to tropical temperature

The rasbora should be ok but the neons are better in a mature tank. Most fish will eat any smaller fish that will fit in their mouth so you need to research which species you can keep together

Thanks for the advice, will hold off on the neons for a while....finding this forum a lot more helpful than "pet shop advice"....One guy told me to get some discus fish with the smaller fish another told me discus will eat the rasborras, and that i should get a couple of choclate ciclids....reckon i will be using this forum a fair bit over the coming months!!

 

[anon02]

Pet shops are in the business of selling product, if your fish get sick or die it gives them the opportunity to sell you medication or replacement fish .... not that I am suggesting that they would give bad advice purposefully of course

 

[Tolak]

thanks for the welcome!...i have many questions.......have gone from "put fish in water and feed"knowledge level to "bloody hell"level in 10 minutes flat from reading these forums...all sounds good though and have just learnt that fish are like any other pet....care and attention required

You are so in the right direction, welcome to TFF!

 

[waterdrop]

I agree with anon02's comments. The goldfish need to be rehomed to a friend's pond or some other situation but the timing of it all could really help you get the big tank cycled and give you time to figure out the new home for the goldfish.

Harlequins and neons are among my current favorites. Harlequins make even better first fish after a fishless cycle than zebra danios do and I also agree with waiting until the tank is a good deal more mature before introducing the neons. A nice big pack of harlequins and you'll have your evenings of bliss seeing a living sunset swimming in the tank (gotta be about the only animal alive that can imitate the colors of a sunset!)

If your tank has about 17" of height (what's the volume?) and 30 US gallons or more then you could think about introducing a pair of angelfish (young ones) after the tetras are well established. The angels will then not usually see the neons as food and you can get by for many years before any get eaten, if ever.

~~waterdrop~~

 

[Kiwi Clint]

I agree with anon02's comments. The goldfish need to be rehomed to a friend's pond or some other situation but the timing of it all could really help you get the big tank cycled and give you time to figure out the new home for the goldfish.

Harlequins and neons are among my current favorites. Harlequins make even better first fish after a fishless cycle than zebra danios do and I also agree with waiting until the tank is a good deal more mature before introducing the neons. A nice big pack of harlequins and you'll have your evenings of bliss seeing a living sunset swimming in the tank (gotta be about the only animal alive that can imitate the colors of a sunset!)

If your tank has about 17" of height (what's the volume?) and 30 US gallons or more then you could think about introducing a pair of angelfish (young ones) after the tetras are well established. The angels will then not usually see the neons as food and you can get by for many years before any get eaten, if ever.

~~waterdrop~~

Thanks , the tank holds 150 litres which is around 30 gallons. The angle fish idea is a great help. really want a couple of bigger fish in the tank...Have been told discus are also fairly compatible with harliquins aand neons.......your thoughts?...