If the liquid test you tried is the API one, it needs to be carried out exactly as per instructions including banging bottle 2 on a hard surface and shaking very vigorously for at least 30 seconds. If it isn't shaken really well, and then the test tube shaken hard for a full minute after the second lot of drops are added it can give false low readings.

If your nitrate is that high, you need to change more water, more often. It needs to be kept below 40ppm, or preferably below 20ppm for goldfish. Because your tank is so small, nitrates accumulate very fast indeed so you really need to be changing part of the water every day to try and keep the level of nitrates down.

A "sucking catfish" could mean any of many types of fish, but unfortunately none are suitable for a cold water tank, apart Hillstream Loaches who are very specialised fish and unsuitable for goldfish tanks.

Hi

pH 7.6 is good for goldfish. They need it to be between 6.5 and 8.5 so yours is right in the middle, which is ideal.

Ammonia and nitrite should always be 0, so that is good.

Your nitrate reading of 0 is worrying. Nitrate is the final product of the nitrogen cycle: it is what ammonia and nitrite are turned into to make them safer for fish. In a cycled tank, especially on with "dirty" fish like goldies you would expect to see a reading for that.

How big is your tank? How long has it been set up? Did you cycle it before adding the fish and if so how?

Just a note too, that sucking loaches are not suitable for cold water tanks. They are a tropical fish who need warmer conditions and they also grow quite large and become aggressive as they mature. Care sheet for these here has more details.

That's Cool Congrats on finishing your education - now is when it really begins

Not really. Shops don't have any real clue as to what someone intends doing with their purchases (living or otherwise). Their duty comes under the terms of their local authority pet shop license and the general duty in terms of not selling animals to children.

There's no way a shop can police customers. The best they can do is ask a few questions, but there's nothing to stop a customer lying (not suggesting OP did).

No it's a mixture I make up and paint onto pebbles then bake in the oven I'll have a look for the post I made about it a while ago.

EDIT

Here it is: Home Made Algae

Yes very new in fish keeping terms. They were first described in 2010 and started appearing on importers lists awhile later.

They apparently breed quite readily and have an unusual method. The female expels her eggs in clutches and they remain attached to her by a sticky secretion and are fertilised in situ. Then she will swim around for quite some time looking for a suitable site to leave them (usually mossy plants) where they are rubbed off and stick to the plant until hatched. I'm hoping to see this in real life if they'll oblige

Interesting.....I picked up four Oryzias woworae at the BCA auction and moved them from quarantine to their permanent tank today. The tank also houses some Otos who I supply with home made "fake algae" painted onto stones. The little rice fish are all over it, so it seems they like to graze too.

Quote:

Very good indeed!

I saw that in my Facebook news feed from INJAF .... makes it very hard to see how the shops justify selling these to the public.

Well they still have some babies at the moment. I've been target feeding hard boiled egg yolk to them with a turkey baster and now the first batch of live baby brine shrimp is ready so FX we'll save at least a few.

Dad was very angry with me this morning when I did a water change