Sick Calico Fantails?

[Aberama10]

I have a 22 liter Ciano tank with a 20-40L ciano CF40 filter. In the tank I have 4 calico goldfish 2 large 2 small, and a golden loach. They have always been of great health I keep up with filter and water changes, I have recently planted my aquarium and it seems to be bringing up a few problems. I’ve already lost one fish (but he was pretty unhealthy when I bought him because of improper care at the pet store, he lasted a good while longer than we anticipated). I made sure that the nutrient substrate I used has been properly covered by just over 2 inches of gravel and I did daily 75% water changes for the first week to make sure the fish weren’t being affected by any substrate that may have released as the gravel and such settled. As of now, 4 weeks later, I have made only 1 water change per week and they seemed to be doing well until today when one of the smaller fish has stayed in the corner at the top of the tank only moving every so often and I’ve noticed he’s not eating as well (and also has always seemed to gulp bubbles every time he tried to eat incase that helps) but now seems and if he’s isn’t even opening his mouth when trying to get eat. I have done a complete water change in the hopes this would improve but it doesn’t seem to have affected him. It has only been a few hours since the water change so should I just wait it out in hopes he will improve or is there something else I should be doing?

 

[Salem]

I am no expert on loaches or goldfish but I do know that a 22 litre tank is far too small for even a single small goldfish, let alone 4 other creatures.

Goldfish need tanks that are are at least 40 gallons (151 liters) and your type of loach needs at least 55 gallons (208 liters). These fish both get very big and need a lot of room to move around.

I think the issue you're having is ammonia. You'll want to research the nitrogen cycle in depth to fully understand, but basically in the simplest of terms fish poop produces ammonia, ammonia (toxic) is converted to nitrites (toxic) by bacteria in the tank, and then nitrites turn into nitrates.
A 22 liter tank is actually a pretty small tank in general, meaning that even with fish that are suited for that size of habitat the ammonia builds up quickly. Goldfish specifically are notoriously messy- they produce an absurd amount of waste which in turn produces a whole lot of ammonia.
One water change a week would normally be fine but with goldfish and the loach you'll want to bump that up to at the very least every other day.
If ammonia is the issue then your sick fish may not recover. Goldfish are very hardy and in my (limited) experience once one actually shows signs of ammonia poisoning it's too late. That being said the full water change was likely the best thing you could have done and should help.

You will want to get your hands on a liquid test kit (the strips are known to be unreliable and inaccurate). This will allow you to test the ammonia, nitrites, and nitrates. You want ammonia and nitrites to be 0 and nitrates to be under 40 if your tank is cycled. If it isn't (which I suspect is the issue here) then you will want to learn how to cycle the tank with fish in it. However I would recommend first finding a bigger home for them and cycling that.


Also, just as a note; having a planted tank is very fun and pretty to look at! However, goldfish are known to eat almost every plant they can find. I'm not saying you should ditch the plants, I'm just saying maybe don't get too attached to them.