My poor aquarium

[Burbage]

RB, it doesn't matter how big the tank is really, you will only ever have as many bacteria as there is bacteria food to eat. Technically, if you add another fish but don't increase the amount of food you put in the tank you may even end up with fewer bacteria, because less food will probably be wasted.

Having a larger tank is more to do with increasing the amount of oxygen it can hold, which is a different thing to the nitrogen cycle. You could build a filter with enough space to look after twenty fish in a one gallon tank easily, but the fish will never have enough oxygen, and, of course, the bacteria need oxygen too.

[Rosbif71]

easier with Bettas as they get some of their oxygen from the air

[Burbage]

Indeed. A jam jar is enough to provide life support to a betta, but quality of life may be a different issue.

[Rosbif71]

thats why I have gone with real plants in there. will move things around in the tank when I do partial water changes as that is supposed to help

[Pinklepurr]

You know Slinky fish tanks are not hard work once you have them set up. I thought that too but my old tank was great, and like Lili I was the one who loved it the most. It really is that initial set up that you need to get right, then it is just managing it, which is way easier than any kids or fluffy pets!

[Lichtgestalt]

which is way easier than any kids or fluffy pets!

And you can simply flush the fish down the toilet rather than put them up for adoption

[Lili Von Shtupp]

OK, I took Burb's advice and got me a mini chemistry set and was really surprised at the results.

Ammonia = zero
Nitrite = zero

So far so good, so I checked for Nitrate level = looks between 10-20 ppm. According to the literature that came with my test kit, a nitrate level of 40 ppm or less is recommended for freshwater aquariums - Burb, you recommended keeping it less than 10 ppm - should I be concerned about my nitrate level?

I also checked the pH, which is 7.0 on the nose, which they say is good for your average community tank.

I did this test before my normal tank cleaning (gravel siphon and water change).

I don't know, I think I was expecting a hot mess in there, but it actually seems pretty good. I'll continue with my normal feeding, cleaning routine, and if the levels are the same next week, then I'll consider adding those cherry barbs. What do you think?

[Burbage]

Add a few at a time. Add three maybe, try not to put more food than usual into the tank and watch your ammonia and nitrite. Then gradually increase the food to the amount required by your new tank population. Remember, fish can go several days without food (weeks for bigger fish) and suffer no ill effects.

Nitrate is much less toxic then either nitrite or ammonia, which is quite handy since the bacteria that metabolise nitrate are anaerobic and very difficult to grow. But, in the natural world, where fish come from, nitrates are almost always zero, because they are used by plants, algae and bacteria.

Also, high nitrates will encourage algae to grow.

With a small tank, it's easy to keep nitrates low. Feed only as much as your fish need and change water regularly. I recommend less than 10ppm, and no more than 20ppm. More than that is safe for some fish, but you'll get algae problems.

[Lili Von Shtupp]

Hmmmm, funny you should mention that. I've been noticing a bit more green than usual creeping up the sides of the tank. I never had quite so much of it before I got live plants, because I never really used the tank lighting system. Now with the plants I make sure the hood lights are on during the day, which I'm sure feeds the algae growth. From what I've read, though, this algae isn't too bad in low doses, and can be easily controlled with regualr tank cleaning and water changes, including the occasional scrape. I've got a rubber spatula just for that purpose.

Thanks Burb. And Morrolan, too.