Nitrite levels

About a month ago i brought a bi-orb. Within a number of days i got my first fish, a small black moor followed shortly after by a red top (?). I tested the water regularly and all seemed fine. However i noticed that the blackmor started to get rin rot. I treated it with chemicals but it didnt clear uP AND EVENTUALLY IT DIED. within a couple of days the other fish died too, but i couldnt find the cause. Anyway i left buying anymore fish up untill a couple of days ago and purchased a medium sized black moor. Now im faced with high levels of nitrite. I have carried out partial water changes, fed small quantities of food and even brought chemicals to reduce but it dosent seem to be dropping. I thought keeping fish would be easy, man was i wrong....help!

Sounds like you've added fish before the tank is cycled properly.

 Biorbs aren't really suitable to house goldfish in. They simply can't cope with the amount of mess that they produce. Goldfish also really need at least 38L (roughly 8 uk gallons) of water each, and even the largest biorb can't provide this for more then one fish. There are plenty other smaller, less messy species that will live quite happily in your tank, such as white cloud mountain minnows, and cherry barbs.. :) 

It does sound like  Dave says, that you've added fish before the tank is cycled properly.. That coupled with the amount of waste goldies produced will probibly give you high nitrite readings.. I've also heard of biorbs that never fully cycle, and so have constant low levels of nitrite.. Cut feeding down to an absalute minimum, and do small daily water changes until the nitrite reading drops off. 

cheers for that. I am starting to regret not buying a more traditional tank. 

 please don't blame yourself, the shop person should of asked you what setup you have and how long it had been running before selling you fish. Did you tell them how long it had been running? Might be best to anyway from now on just incase they or wherever don't ask.

Just say I have a blah blah tank and it's been running this length of time, can i put this or that in etc.

To be on the safe side ask here first then you have some idea of what the tank is capable of holding before going to any shop  

horrah. sorted the nitrite levels. they are coming down. good advice from a good pet store. however the fish have got white spot. i am treating it with a white spot medication. how long does that take to clear up generally? Could the fish die?

for whitespot follow the instructions but also raise the temp to 30 degress (for most heaters the max)

i noticed you said a black moor and a red top...i'm wondering what the red top is...

redcap oranda?

i hope so, was worried it was an african...

doh, i meant redcap