newbie, advice/comments appreciated :)

yellowbrickroad

Hi, I'm a complete newbie to fish keeping. I've recently bought a 20gallon/90 litre tank and have it set up with sand as the substrate,and the heater and filter that came with it (aquael internal fan 2). I started the fishless cycle 4 days ago and it seems ok so far, my ammonia went from 5ppm to 1ppm in 3 days and I topped it back to around 4ppm today. The water went cloudy a while after adding the first ammonia but is now ok,
although when I use the air tube thing (sorry don't know name) on the filter to make bubbles the whole tank fills with tiny bubbles and looks dirty, which I first thought was my sand being messed up.. so I've turned that tube off, will the water movement from the filter alone be enough? Do I need an air pump/stone?

My main question is about stocking, but if I've said anything that sounds wrong I'd appreciate being told. So I've used sand as I really want corydora. I was planning on 6 of a small species, maybe 3 trilineatus and 3 panda. But the book I have said they're not good first fish as the tank needs to be more established. So I was thinking of 5 or 6 harlequin rasbora to start out (after cycling), and then the corys, but I would also like a little school of neon tetra.Would that have me over stocked? Is my tank too small for the corys?

Water parameters before starting cycling were ph 7.2, GH 16, and my nitrates in my tap water were pretty high, about 30-40 :/ they've dropped a lot now in the tank, don't really understand why? But I plan to have live plants so I hope that will help any nitrate issues, and if not I've bought a thing to attach to the taps to remove nitrates.

Thanks for reading and any comments/advice are very welcome :)) many thanks.

thekoimaiden

Hi and welcome to the forum! Kudos to you for starting out with a fishless cycle!!

About the bubbler, the filter will provide enough movement through the tank. You don't have to worry about turning the air pump on if you don't want it on.

Now to your stocking questions, personally I think two schools of column fish in a 20 gal would look a bit crowded (this is excluding the cories... I'll get to them in a minute). Instead, try doing one large single species school (10-12 fish) instead. These small schooling fish naturally live by the thousands in the wild. The larger the school, the more colorful and visible the fish will be. So chose whether you want neon tetra or rasbora; personally I'd go with the rasbora as they seem to be much hardier than neon tetra which have been subject to a lot of inbreeding recently. The alternative is wild-caught neon tetra which would not do well in your hard water.

About the cories. They will really really appreciate the sand! As for the grouping, again I'd go with one species and have 6-7 cories. Three of a species is the absolute minimum that should be kept together, and even then sometimes people report them being shy even tho there are other cory species in the tank. Since it's your first time and we want to keep this tank as low-stress as possible, just pick one cory species. Bronze cories would be my first pick since they are so hardy.

fairghum

You will love having cories. They are so cute and can really get into your heart, sitting on the bottom winking at you. If you're really lucky, they will breed in your tank. It's easy to get attached to the cories!

squishylittlefishies

Yeah, for the cories, choose a bigger goup of one type, because the different species won't shoal together. I would not reccomen pandas as starters because they tend to be more sensitive, but the other kinds should be ok!

yellowbrickroad

Thanks to you all for your advice :) I'm glad I don't need the bubbler my water is clear without it, and I have movement on the surface. I think I'll go for a bigger school of the harlequin rasbora then, as I prefer the way they look and from what I've read they sound hardier. Should I start out with had the school then double it a few weeks later or add the whole school at once?

I think I'm going to love corys too:)) I'd read in the profile and in the cory page on this forum that pandas are sensitive, I just think they're so cute.. but I'll be sensible and pick an easier species for my first tank. I think if I'm going all one species I'd like trilineatus as I think they'd look really stunning with the rasbora.

Should I be worried about the high nitrates in my tap water or will the plants sort it? I haven't tried the device I've bought yet but I'd rather have not relied on it in case it breaks at some point and then I'm suddenly adding higher nitrates with my water changes.

Thanks again :)

yellowbrickroad

Looking again at the profiles for the fish I want I see my water is too hard for the trilineatus :( is there anything I can do to reduce the hardness?

Thanks again.

fairghum

Just remember your tank is only 20 gallons. Don't overstock it! Your small fish from the fish store will get big!! I have a 20 gal w/ 5 gold barbs, a dwarf rainbow, 2 cherry barbs and 2 cories and feel like they're stuffed in there.

yellowbrickroad

Thanks fairghum, I just used aq aquarium calculator for 10 harlequin rasboras and 6 peppered corydora and it said I was about 75% stocked. It says I'd also be ok with a little school of pygmy corys, which I adore, but I like the suggestion only having one schooling fish in the column.

(Btw I'm looking at peppered corys now as the profile says they're ok with medium hard water. I really want trilineatus but don't want unhappy fishes ;) )

fairghum

I had peppered cories and they had beautiful babies in my tank. 8 or 9 babies survived, and were SO cute!! where did you find an aquarium calculator that tells you how many specific fish of which breed can be in a particular size tank? Might make me feel better...

yellowbrickroad

It's aqadvisor.com I read it on someone else's post. The peppered corys look really cute :))