I've got a few questions that I could really use some help with as someone who is new to all of this. If you have some time to help, I'd be incredibly grateful. I'm spacing it out under different headings for ease.
New Tank
I've purchased a Aqua 30 tank that's 24 Litres. I'm being told many different things about how many fish I can safely hold in this size tank, and it seems from most posts on the Internet people either have a lot smaller (bowls) or a lot bigger tank sizes than mine, so I can't seem to figure a rough amount out. I'd like some Neon Tetras (I do have a heater, already heating up the tank as I type) and maybe some Zebra Danios, as I've heard both are hardy fish. Will these two species live together and how many is recommended? I don't want them to suffer due to Ammonia poisoning or over-population.
Nitrogen Cycle
Someone explain this to me in basic terms. I'm mostly confused because most descriptions of it are using American measurements and I'm in the UK, so it's puzzling me further. I was told by the shop that a week is enough to power a nitrogen cycle through my size tank and to add food to it to help it on its way. Is this correct information? As it's described on here, treatment things are needed to speed it up - because my tank is quite small, how long would it take to reach a sufficient point in its fishless cycle on its own?
If that is not the case, can someone break it down for me into something that I can do step by step with this page open? Most explanations seem to diverge onto different topics mid-flow or give me products I can't buy in the UK...
Filter Problems
This might just be me, being someone new to all this, but I'm not sure if my filter is functioning correctly. I can't identify the brand of filter specifically, as I have purchased it and the tank from a friend, but I know that the filter came with Mars Fishcare Europe Rena Crystal Cartridges Size 1, if that means something to anyone?? I've put the Cartridge in the top compartment, the black mesh material in the bottom compartment and set it off. Only thing is it doesn't seem to move a lot. I can see water cycling, but not at any great speed. Is it supposed to be quite slow? I imagined if it needed to clean out Ammonia etc it would need to have some speed to it! It's fully submerged roughly 2 CM below the water line currently and there's very little to see for flow coming out...is this normal?
I know that, being new to this, it's trial and error but I don't want to end up with what is described as New Tank Syndrome in my first few weeks. Any advice I would be grateful for, I feel like I'm banging my head against a wall lol.
Thank You for reading and feel free to remove this post if it isn't allowed...