How Long Can I Keep Fancy Goldfish In 60L?

As title really. I always wanted celestials, but couldnt find a stockist, then, low and behold p@h had 'telescopes' that seem to actually be celestials. They had them in with some sort of loach that kept sucking their eyes I resisted for a week... but went back to see them and they looked terrible, most could no longer swim properly, so I gave in and got 2.

Now I only have a 60 litre, but figured this would be okay for a while till I got a bigger tank.

How long will they be okay in here? I have 2 and they are less than 2 inches currently (edit: one is about 1.5 inches the other about 1.8inches), and I'm a little worried that they havent grown that much since I got them about 3 months ago, I guess they may have been stunted already by the supplier? How quickly should they be growing? Realistically I can't upgrade till the summer, as I dont think my current flat floors could stand a big tank, but when I do, how big should I go (that doesnt have to be on the ground floor)?

And one last thing - am I right in thinking celestials wouldnt do well in a pond because of the cold?

Bumping this up, any advice would be welcome

Sorry I managed to miss this1

You're right, celestials aren't suitable for ponds. They should have grown some by now; you'll need to be doing lots of large water changes (at least 50% twice a week) to dilute the hormones they produce that stunt their growth.

You need to move them to a larger tank as soon as possible; a three foot/120l would be fine for them

They are beautiful fish, I have one, they are not often found and usually sell out fast, mine was the size of yours when I got it, now it is the size of a chicken egg it's in a 60l. I change the water often and give it a variety of flakes, live food and frozen they are very greedy and love greens too, I have a load of duckweed at the mo and he's loving it! the temp is about 22 degrees, they are more sensitive to cold than other types of goldfish but also don't like tropical temps, let me see a pic of yours

Thank you!

Ooops, I've been doing a 60% every two weeks, as I was understocked as they are so small, didnt realise about the hormones.

What foods would you say are best for growth?

I've had the tank at 18-19 celsius, is this too cold? I didnt want to keep them too warm as you always read everywhere about how bad it is for goldies to be in tropical tanks. I havent had goldies since I was a kid, due to not having a big enough tank, so I'm very rusty in my knowledge on them. I have a heater in there though as my flat temp fluctuates so wildly, so I can easily turn it up?

Are yours terrible at finding food? Mine are. And do you provide surface plants for cover? I was worried about their eyes being constantly looking up, but when I got amazon frogbit they ate it so much it died!

I'll upload a pic later, they're on my phone atm. I only have a pic of one I think though, the other wouldnt stay still!

Foods are tricky with celestials, as you have to use ones that float; I'm sure you've noticed yours can't pick up food from the bottom! Might be worth looking in the pond section, as most pond foods are designed to float so people can watch the fish feeding.

That temp is ok, but it's the bottom end; a couple of degrees higher would be better.

Cover in the form of floating plants would be good, but they'll probably eat everything you try! Java fern might be worth a try, most fish won't eat it, and it should be able to grow floating, or maybe attached to ring made out of airline or something?

I found mine seems to be better at finding food since getting older not sure why this is, maybe it's the bigger mouth or the bigger eyes he picks up food from the substrate no problem his sense of smell is second to none! they do have a habit of over eating esp when larger so be careful with pellets or anything that absorbs water and expands, I lost one once that ate a few too many bloodworm pellets that I fed to the other fish in my tank, a lesson learnt
As long as the diets varied and the water kept clean, 25% weekly should be fine, they grow well, mine does not touch my Anubias, Amazon Sword, Java Fern or Java Moss so these plants should be ok with yours Around 21/22 degrees is fine I don't have any floating plants in mine apart from riccia and duckweed that gets eaten! I only occasionally put the lights on as the aquarium is in the conservatory which is quite bright but there is a large pot of Amazon sword in the middle and bogwood to shelter under if the lighting gets too bright.
The big guy George in the pic is the one that died the smaller one poly I still have, he/she is now as big as George

Loving the pics! I cant seem to get mine off my phone, as my rabbits chewed the cable

my two weirdly cant seem to deal with flakes, one doesnt bother at all and the other one occasionally tries after a while but just gulps blindly at the surface for ages, surprised he didnt get something like swim bladder from it. So I usually use sinking pellets and they just go nuts nomming randomly on the gravel, they dont seem to be able to fnd them well but find them in the end.