Bi-Orb 30L Advice

[fishman101]

Hi there, I have no idea if I'm writing this in the right place. A friend of mine owns a bi-orb 30 litre tank which I believe is freshwater. Recently her fish died in unusual and tragic circumstances and I want to buy her some replacements. Unfortunately I have no knowledge or experience of the art of fish keeping. I was looking at finding some characterful invertebrates such as shrimp or crabs as well as some good looking fish. Unfortunately I'm worried about which can interact with each other and whether the tank will be the right size / right type of water. I'd be very appreciative if someone could give me some advice here.
Thanks

[malakye]

30litres is really small and bi-orbs have a really narrow top which reduces the number of fish you could keep in there as well. So you know if it has a heater as that will determine what you can add. If it does and has a mature filter then some cherry shrimp and neons make a nice splash of colour and work well, just get a group of about 6 fish as they dont do well in smaller groups than that. You can add a dozen shrimp as they do not add to the bioload of the tank, just make sure there are plants and things for the shrimp to hide amongst.

[fishman101]

Hi there. There is a heater but I'm not sure what you mean by a mature filter, sorry I really am new to this. If you mean a filter that's been used for a while then that's definitely the case. I'm currently looking at these as an initial purchase:

Yellow-Yellow-Snakeskin-Male-Guppy.html
Endler-s-Guppy-Orange-Male.html

Threadfin-Rainbow.html

15-x-Assorted-Shrimp.html

Is this appropriate? Will the bigger fish eat the shrimp? If not can I just add these all at the same time to the tank. I read somewhere it can be bad for the acclimatisation if you add too much at once.

[malakye]

I edited your post as we do not allow advertising. Personally I would avoid mail ordering fish as you never know what you will get.
I would leave the guppies out as they get too big for a 30litre bi-orb the endlers would be ok, go for a group of 4. Threadfin rainbow fish are to delicate and need more water volume than the orb has so again I would leave those. The shrimp will be fine though.
With the tank being tiny you can only add a few fish, if you add too many it will just crash and you will end up with sick fish. Stick to just 4 or 5 endlers and the shrimp.
Make sure the owner of the tank has a test kit so they can test the water stats as shrimp can not tolerate ammonia or nitrites, those need to be kept at 0. Weekly water changes of 25% are a must.