It was not to be. 
my ph is okay though. I'm mainly going to have some rocks and caves for them to hide in, what plants should i get??
If you get two, get them at the same time. I got one, waited a week and the got a second. 5 minutes into the new fish getting into my tank, they squared off and my old one got the best of the new one. I had to return it immediately, which caused me some degree of sadness. I wanted the gouramis as my "centerpiece" fish and since they are so small, I figure two would be better than one.
15 Gallons isn't a lot of space for two of them. I'd stick to only 1. Also I wouldn't go with the cardinals, Id go with neons instead, as they stay smaller. They are susceptible to new set-ups, so give it a bit of time to settle in first.
scrap the silver tips. They need to be in schools of 6 or more, and they can be aggressive.
If anything, just add more green neon tetras. 6 is the minimum number, but the more the merrier. You'll see better activity and happier fish with bigger schools. It also looks a lot better to have 1 large school rather than a bunch of small ones.
I'm also going to have to disagree with getting 2 gouramis. It takes a stroke of luck to get two to get along, regardless of gender. I have never been able to keep a gourami with another gourami, ever, without a lot of fighting leading to death or at least separation, they're almost as bad as bettas, and worse than any cichlids I've ever kept. There are cases of gouramis getting along in tanks, but it takes a lot of careful aquascaping and a good ratio of males and females.
Stick with one, you won't regret it.
With your tank, I'd try for this
1 dwarf gourami, or honey gourami, those ones are less aggressive
~8-10 green neons, think would do
6 otos
Keep in mind otos and neons are somewhat fragile, and you'll need your tank to be well established before adding them.
Gouramis are also prone to territorial aggression, and you'll have to add it last.
So this means a good fishless cycle is in order.
You can read about those in the beginners resource section
Alternatively, try for different fish
1 gourami
6-8 harlequin rasboras
6-8 corydoras
I think this would work too
But if you take this route, sand substrate is your friend, not gravel. You can get any old play sand from a hardware store, give it a good long rinse, wait till the water runs clear when you run your hand through the sand, and your bottom feeders will thank you
No to zebra danios. They should be kept in 4 feet tanks, they're very extreme swimmers, it's not good to keep them in smaller tanks.I'm also going to have to disagree with getting 2 gouramis. It takes a stroke of luck to get two to get along, regardless of gender. I have never been able to keep a gourami with another gourami, ever, without a lot of fighting leading to death or at least separation, they're almost as bad as bettas, and worse than any cichlids I've ever kept. There are cases of gouramis getting along in tanks, but it takes a lot of careful aquascaping and a good ratio of males and females.
Stick with one, you won't regret it.
With your tank, I'd try for this
1 dwarf gourami, or honey gourami, those ones are less aggressive
~8-10 green neons, think would do
6 otos
Keep in mind otos and neons are somewhat fragile, and you'll need your tank to be well established before adding them.
Gouramis are also prone to territorial aggression, and you'll have to add it last.
So this means a good fishless cycle is in order.
You can read about those in the beginners resource section
Alternatively, try for different fish
1 gourami
6-8 harlequin rasboras
6-8 corydoras
I think this would work too
But if you take this route, sand substrate is your friend, not gravel. You can get any old play sand from a hardware store, give it a good long rinse, wait till the water runs clear when you run your hand through the sand, and your bottom feeders will thank you
So, with the oto, should I use sand or gravel?? So, here's my current stocking plan, tell me what you think:
-1 dwarf neon gourami
- 6 oto
- 5 neon green tetra
- 3 ghost shrimp
Is there anything else I can add to the tank??
Edit:
This is a possible stocking i found that i like, what are the negative things with this setup??
-1 dwarf neon gourami
-6 oto
-3 ghost shrimp
-5 neon green tetra
-2 endler
-5 nana rasbora
-5 zebra danio
aq advisor says this places my stocking level at: 89% so how does this plan sound to everyone??
