I'm really embarrased to say this, but my excuse is that I just basically took over my daughter's tank, because she has so little time for it. It was a 10G housing these 4 fish, and she had bought a 16G to rehome them. I knew absolutely nothing about FW fishkeeping, having had a 125G marine tank 20 years ago. When I had trouble cycling the tank, I googled the problem and stumbled onto this forum, which I love, BTW, and found Eco's fishless guide. So I was able to cycle the tank in a few weeks, and get the little monsters out of the old tank.
Now that I know a little bit more about FW fishkeeping, I know we need a much bigger home for them. And they WILL get it, as soon as I am able. But they have survived in the littler tank for all this time, without any water testing, except for pH, and without a rigorous PWC schedule, so I'm hoping they can hang on just a little bit longer, till I have the almighty $$.
I have the original Aqueon 20 filter plus an AquaClear 50, for filtration. And I'm doing 50 -60% PWC every 4 days. The chemistries are all good, except the trates which won't stay below 40 for longer than 4 days. I'm falling in love with the little buggers, so I can't give them up, and I will get more clown loaches, when we have our much bigger tank.