I'm worried about removing the undergravel filter as I think it's probably pretty bad under there. It's small sections that clip together - would you advise a full strip down or just shuffle everyone along?

We have now set up a small quarantine tank which is currently holding 3 fish all with the advanced stages of the problem.

There are a couple of plecs with the first stage (small white markings) in the 6ft tank which we keep trying to catch but they are very quick on their fins so 6ft tank gets ...

Sorry, MrR, you're correct. I meant nitrite is 0 and nitrate is 40.

Thanks, Barbie. I might see if we can set up a small quarantine tank this weekend and then remove any fish straightaway that have the white markings on them. This will determine whether other fish are causing the problem to get worse or whether it's part of the "disease". This might help us come to ...

Thanks for your replies. Ok, here goes.

1. Water parameters
a) Temperature range = it has been quite hot here this last week so the temp went up to about 34c but it's usually about 24c
b) pH = I believe it's about 6.9 (we have to use crushed coral to maintain this pH as it is naturally very low in ...

Hi all,

I have had a problem in my 6ft tank for about 2 months now and I wondered if any of you might be able to advise me please?

I introduced some new fish (weather loach) into my tank and within a week little marks started appearing on my bristlenose plecs. They looked like little gouge/bite ...