Eau, i found out what the smell was...

[Marne]

So after cleaning the filter and doing a huge water change the smell of onion was still in my tank, turned out it was a new ornament that I had bought at pets at home even though I had washed it several times before putting it in there. I lost 3 of my fish and still might lose more, have been doing big water changes everyday to try and get rid of it (the smell), I'm not happy, the ornament (log with holes in it) has been removed and I have tried soaking it, cleaning with boiling water but it still smells, I'm tempted to go and complain to pets at home .

On the plus side, all the water changes have made several of my fish give birth so I know have lots of babies .

Sorry about your fish. :(

I've never heard of any problems with resin tank ornaments, it's worth taking it in though, it could be a dodgy batch or something and there might be more of them.

have you tested the water?

Water is testing ok, there was a tiny trace of ammonia when I cleaned the filter but was only a trace (was hard to tell as the test was only slightly showing as a bit green rather than yellow), all is ok now but it would be with all the water changes I have been doing (I think im going to have huge muscles from lugging buckets of water about), no more deaths since removing the ornament, theres still a slight smell but I guess this will go with water changes (is very slight). Fish look much happier this morning but my tanks looking a bit bare after loosing a couple fish (1 mollie and a couple guppies), all my bottom feeders seem to be ok (corrys and plecs).

Take it back to Pets At Home.

They will definitely want to know about this and have excellent customer service. If it is a risk, it needs to be withdrawn.

Disclaimer - a young relative works there and have just shown him your thread.

I would take it back. The staff at my pets at home are lovely, seem really well trained. So I am guessing that is the ethos of the company.

I will take it back when I go that way on Tuesday, I didn't pay much for it, it was on offer, I bought it for my plecs to hide in ( it's like a hollow log with little holes in it), the more I wash it the worse the smell gets, maybe it was becuase I used hot water? Maybe it effected the paint?