New Tank Set-up (questions On Inhabitants!)

HI everyone, I've been lurking for a few months getting information for my first (real) tank!

I've got it set up for the most part, it's a planted tank with SeaChem Fluorite Dark substrate, a dragonstone, and two acrylic(?) decorations. The two plants I have in right now are a Java Fern (windelov) and a nymphiodes hydrophylla (taiwan type?).

I have been using SeaChem Prime for conditioner, and their Stabilizer for cycling.

The tank is does not have a CO2 distributor, and I don't intend to add one at this time. I've been told, and mostly confirmed online, that neither of these plants require much CO2 or light. I've seen a little arguing about this, but not much. I have been adding SeaChem Flourish as per the directions on the bottle.

The tank is a 20 gallon high, I think. The dimensions are about 24" x 13" x 17" (sorry, everyone here seems to use imperial and I'm used to metric!). I currently have a plain hood with built-in LED lighting, the tank is situated near a curtained window, but no direct light as the window faces north, and it's pretty much winter here 10 months a year.
I have a 100 watt heater that has the water up to about 76F.
I have a chemical and biological filter going; the chemical filter appears to just be carbon. From what I've read, I'm not 100% sure. I think it cycles 150/hour.

I'm basically ready for fish, but I'm not 100% sure which. I definitely want corys, specifically Panda Corys or JuliI (false JuliI is fine!), which are schooling fish from my understanding. Would 4 be a good number?

I also really want an upper tank schooling fish, like Tetras or Rasboras. Even guppies are cute. But they're very small. I really like the harlequin Rasboras. I've seen people suggest 6 of them.

The LFS recommended white cloud/mountain minnows or danios to go with corys.

Questions:
1) Does the carbon-chemical filter need to be replaced with something else as carbon removes trace minerals the plants want?
2) How does stocking look, and does anyone have suggestions? I want an active tank!
3) What food should I get? I have heard a lot of mixed talk about flake food vs granule (I did originally get this tank for a telescope gold fish, but I decided against it as I would then only be able to have one)
4) I saw sand was best, but my LFS told me that was a terrible idea, and sold me on the Flourite substrate because I wanted a planted tank. Will this substrate be okay? It doesn't seem too sharp for the bottom dwellers?

 

Not white clouds. They are a minnow so they are nippy and they need cooler temps.

 

Not white clouds. They are a minnow so they are nippy and they need cooler temps.

Thanks!
I wasn't sure they'd look good in my tank set-up anyway!

 

I would reccomend guppies for your upper tank, but if you're not looking to breed them then male guppies only.

 

1) Carbon eventually becomes inactive (usually after about a month) and inactive carbon is just like having a bunch of rocks in your filter. I tend to use carbon when I'm first setting up a tank or after treating with medication, but not for normal tank use. I would just leave your carbon in there and not replace or remove it.

2) what about 8 panda cories and 10 neon tetras? You could also keep some guppies if you'd like, but I'd recommend keeping only one gender since live bearers breed like rabbits.

3) flake vs pellet vs any other type doesn't really matter since your fish can adjust to accept different types of food. You generally want to look what's in the food (%protein, %fat, etc). To contradict what I just said though, I would recommend sinking wafers for your cories since obviously they can't eat flakes for instance

4) your substrate is fine. Frankly, I think you are overdoing it for the plants; neither of those plants really needs anything special (heck my java ferns keep dropping pups even with ferts, not rooted to anything, and not a full spectrum light) and I know how expensive some of those things can get.

 

I would ditch the carbon and add more plants. Even low light plants help more than the carbon will

As for your stocking: I wouldn't keep cories in a tank with that substrate. I can't be sure but from what I remember, Fluorite is pretty "rough" and as such, would damage your cories' barbels. Cories really should only be kept in sand, as they are sand-sifters.

I would stop with the ferts, because the plants you have aren't going to use them, and you'll end up with algae. If you do get more plants, you can start ferts again.

Okay, so on to the fun part: stocking.

Since I really, really don't suggest getting cories, how would you feel about a clown pleco? They're pretty, and interesting, and the only special thing they need is a piece of real driftwood.

Neons are really sensitive little fish, and I generally find them to be unhealthy in most stores near me. You're obviously not in America, so perhaps it's different where you are and you're able to get wild-caught ones, which would be great. You could also do a single centerpiece fish, such as a gourami, or if you want to stick with SA species, a small cichlid.

 

I would like to add on the subject of neon tetra's that they are much more lower/mid swimmers than I expected them to be. In my experience they tend to swim around all the ornaments I have on the bottom and barely get into the mid section of the tank. And that is with almost the entire surface covered in floating plants! After looking into local availability I arrived at glowlight Danio's, which should be more mid/top dwellers, but I haven't gotten them yet.