First of all thank you all for commenting on my previous post but the situation has worsened

I have found out I have a water problem so I have stopped feeding the fish now for over 48hrs as there was so much mushed food floating around when I arrived home this everning I found one out of the three fish I have dead it was fluffed up by the tail and sucked into the filter.

I then tried to remove all the other mushed old food and I have removed the fish but still the tank has lots of bits floating around. I have changed 50% of the water but it is still cloudy from an angle

The 2 remaining fish are just hanging around the filter I even changed the position of the filter and they have gone to the new side it is on. The filter is still sucking in the remaning food I haven't managed to remove. They seen very slow compared to what they use to be like

I used green remover for aquariums also even though it has not worked maybe it has poisened them I don't know but would very much appreciate any persons help thanks to everyone who reads or replys I don't want anymore of my fish to die its not fair for them to suffer

Tanks are real easy to give problems, I will try to help you sort through them.
The fish may be hanging around the filter because the water going back inside the tank is delivering the oxygen they need.
Lower the water level by 2 inches so that the water filtering back inside the tank creates bubbles in the water. (you don't have an air pump right?) you should really get one if you haven't already.
I noticed that you read about the aquarium cycle, so I'm guessing that your cloudy water is due to the cycling process. The beneficial bacteria clouds the water before it builds into colonies.
You probably have a very high ammonia level and that's why you're losing fish.
The fuzzy puffiness is normal for a dead fish.

Before your problem occurred, did you do any significant tank/filter cleaning and/or a large water change?
Over cleaning an aquarium is the #1 cause for problems along side the initial cycling process.

What size tank?
How long has it been running?
Did you do significant cleaning
And do you have a water test kit yet?
What the condition of the tank now and do you have a bio wheel or sponge inside the filter along with the debris cartridge?

The Tank Size is 30litres and all my problems did begin when I did a water change a week ago. I've had the tank for 3 weeks and the three fish have been fine. When the first one died I did a mass water change 50% and tried to clean the tank it has cleared now about 90% clear but this mornin sadly one out of the remaining 2 was dead. I do not have a water kit yet I have a sting ray filter

Elite Stingray Internal Filter - 3 models (http://www.everythingforpets.com/elite_stingray_internal_filter_3_models.pet/use.id.5.item_id.6397.dept.1200/)

That is a link to it. It is stingray 10
Thank you for your advice so far and hope you know the problem

Hello again,
I believe, since your tank is new, it never fully cycled yet.
This is a lengthy process taking between 4 to 8 weeks if done naturally (no bottled bacteria supplements)
You added several fish all at once, and in a new aquarium that has not cycled this causes the water to become to polluted for the fish to live in.

It's best to start with one or two fish until the tank has cycled.
After it cycles, you will not have the pollution problem but you will have to watch out for over cleaning.