Just Picked Up 4 "mystery Fish" Today, Sort Of Id'd- Nee

[Tokis-Phoenix]

Well today i picked up 4 "mystery fish" from a 30gal today, im hoping to pick up the 30gal they came from soon as its a very unique design, but im stuck with the fish for now- i took them in because the guy who owned them was gonna give them to the lfs if i didn't take them, which is an aweful lfs.
Well as far as im aware theres 2 small/ish goldfish(about 3-4inches, about 5yrs old, dunno what type they are), 1 opaline gourami and 1 molly. The gourami is acclimatising in my uk 10gal(just has some oto's, snails and a shrimp) until i get can some advice on what to do with it as i have heard opaline gouramis can be quite agressive, so im not risking it in my 125gal until i know what to do, and the molly is in my 30gal quarentine tank; im gonna set up the goldfish a spare 30gal hex in a mo as im not happy about keeping them in tropical temps even though they have apparently been in a 28degree hot tank for the last couple of years, soo...
Now for the advice ;
a. How agressive are opaline gouramis? My stocking for my 125gal is;

125gal tank: 25guppys+, 12 platys, 10 pearl danios, 24 neon tetras, 4 albino corys, 4 peppered corys, 4 panda corys, 9 WCMM, 1 RTBS, 5mollys, 1 7inch common plec, 1 8inch common plec, 1 10inch sailfin plec, 1 6inch chocolate plec, 1 4inch para plec(L075 i think).

Would an opaline gourami be ok in this sort of setup, or best not to risk putting it in? Its quite a large gourami, im guessing 5-6inches, dont know what gender it is though.
b. I dont know what type of goldfish i have- all i can say is they are pretty bog standard looking 4inch(or so) orange goldfish, the type you'd probably see been given away at a fair, they are not very fancy looking- no big eyes, forheads, massive bellys or anything but their tails are quite long. Anyone know what they could be? I dont think they are comet goldfish as i would have expected them to have grown more in 5yrs.
c. Im gonna set up a 30gal in a mo, would it be ok to put the goldfish in water heated to about 20degrees? They've apparently lived in tropical temps their whole life, should i just lower the temp slowly over the next couple of days/weeks?

 

[Weaver]

I can only speak from my own experience .Ive kept opaline gourami with all those fish except the plecs.Ive only ever seen mine get aggressive with another opaline and a big fancy sailfin molly that I had.Both opaline were male.Btw it never bothered the ordinary mollies.
I have bristlenose plecs in with my opaline at the minute and they just completely ignore each other so it may be the same with your plecs?
Sorry,cant help any with your other queries.

 

[Tokis-Phoenix]

The gourami is now in the 10gal either way, it looks like its just settling in- i can always move it to the 125gal when ever though either way- the goldfish are also now in their own 30gal, although they seem to be 2 separate types.
I think i've also ID the 2 goldys, one is just a common goldifsh and the other looks suspiciously like a comet, although its hard to believe its a comet as its at least a couple of years old and i thought they grow really big ?

 

[MishyTheFishBreeder]

Nice pick up on the gourami. From my experience with goldfish they only grow to the size they feel comfortable in the tank so they wont get to big if they are in a 30gal. They might grow a bit more it all depends.

 

[jkrekord]

you could move the goldfish to an outdoor pond lol
i would move the opaline gourami to the 125 gal

 

[Arfie]

With regards the temp, I think I'd put them in at 26°, then knock 2° off each week until you get them to the temp you want. If they've been living for 2 years+ at those temps anything too quick could just finish them off.

Good luck Tokis and well done

Arfie

 

[Tokis-Phoenix]

Thanks for the advice, all for of the fish are settled in now but they are very shy, im thinking of moving the gourami to the 125gal tonight, i was wondering though, what are the chances of it gobbling up all of my livebearer fry?

 

[Weaver]

I would think that its very likely that it would eat the fryif they are small enough to fit into its mouth
I had a quite large fry die the other night and threw it into the(mainly) livebearer tank to see what would happen.My rather small pearl gourami swallowed it in one mouthful.
BTW the fry wasnt diseased-it had got stuck behind the filter

 

[Tokis-Phoenix]

Hmm....I know its not really fair to keep the gourami in the 10gal for the time being, but i would prefer waiting until my 30gal quarentine tank is a little less stocked and then put it in there, and then maybe finally move it into one of the new tanks when i finish my kitchen- i know most people dont like livebearer fry as they often get too many, but its been a while since so many fry were in my tank thriving in my main tank and i sort of want to raise a couple to adulthood before i put any fish in there that could eat them- thanks for the advice .