We are looking a new fishy friend for our goldfish who lost her friend recently.
Now I really love the goldfish I've seen at our local fish shop, some are the same size as our Lily, but it was my daughters fish that died and she wants to buy a Pictus cat, I have googled it and tried different spelling but I can't find any info on it anywhere.
She really fell in love with it! I don't know what I'm going to do.
The man in the shop said that they should be fine together but I wanted to know more about it first before going back to ask the man more questions about it. Don't want my daughters hopes getting higher!
She even told the fish man to keep him for her! Not sure if he will though.
The fish shop owner has a great reputation, so I'm sure he is right, he just said to introduce him very slowly, a tiny bit at a time.

My son on the other hand owns our Lily and he wants a snail or something a bit different for the tank, do you know of anything that might suit?

I just want another Goldfish, I've seen lots at the fish shop that I would love to buy!

Is our tank big enough for all of these? It's 110 litres.

Catfish in general have different needs for their environment, different water quality and temperatures suit them, as most of them want rather soft and warm water, like tropical fish. Another thing is that they might start eating the slime coat of goldfish, and  that would, if left unattended, easily kill the fish.
Besides, most catfish grow big, and most of them enjoy company of their own species, so I would strongly advise against these...

Snails should be fine, though! There are plenty of pretty snails that you could buy But they will be a pain to get rid of later, since most snail lay eggs absolutely anywhere and everywhere.

I think I read that Lily is a common goldfish, right? In this case, you should get her, like Hanna mentioned, another streamlined goldfish as a friend, such as comet or shubunkin, which are both real beautiful varieties These are most compatible as they are all quite boisterous and will easily compete for food

From everything I've read and heard, goldfish are best kept with other goldfish because of temperature and nutritional needs as well as the dangers of them catching diseases from other species (koi in particular).
It is also best to go with the same general body shape.  If you have a common, comet, or shubunkin, keep them with long-bodied fish.  If you have an oranda or one of the other "round" goldfish, you should keep them with the same type.  The danger here is that the round-bodied fish are usually slower swimmers and might not get enough food.
That's my two cents, anyway...

Thanks for all of your advice.
When I typed in Pictus Cat I did get lots of info on catfish, just couldn't find it specifically, I was reading lots of mixed things about catfish, some are ok with golfish and some aren't, it's v confusing.

Anyway I thought it best to ask here, as my priority is for Lily.
I like the idea of letting my daughter pick the catfish and putting him in the smaller tank and I could pick a friend for Lily for her tank.
My kids birthdays are coming up within two months time, so they could buy a bigger tank then for the catfish my daughter wants and snail or crab that my son wants.

That's that sorted then! Thanks!

Now, where am I going to put that other tank? lol.
Ooh, I know, I could remove the tv from kids room and put the tank on the tv stand, hee, hee.

Don't get a snail!!!! They destroy tanks even more than goldfish do and they don't need another snail to have babies so soon your tank may be filled with snails!

Lol. After reading that, I'm going to say to my son, my son may change his mind on the snail.
Thanks Mindemae, the Pictus catfish does look very sweet and friendly.
We'll have to see what we end up with and where they all end up. lol.
At least I have two tanks now!

But some snails (all I think) don't require a partner, they can have babies all by their selves.