i have since started my tank again after problems with air freshner! everytime i put the lid on and use the lights my fish become stressed and lose their colour and develop fin rot. The tank is second hand and was used before as a marine tank it has a uv marine light in it and i was wondering if maybe this is the problem the fish in question are 2 goldfish but i have also lost danios and mollys

I'm not aware that UV lights cause these sorts of problems. It's more likely to be down to poor water conditions. You could try leaving the lights off and seeing if it makes any difference. Remember that the lights are really only for our benefit, the fish aren't going to feel the effects of no lighting.

it might also be an issue with the brightness in the tank.when i first got into oscars i had very mild lights for them. after a while i increased the lighting and they looked a little stressed from it(no fin rot though). after a week or so they got used to the new lighting and all is well now. marine lights might be more intense than the lighting they were used to. also most marine lighting is designed to help in coral growth so you might run into algea problems later.

you should still, as a precaution, test your water to see if it fall into the accepted parameters

The fish were fine for a week with no lid then as soon as i put it on this happens.On the light tube it doesn't say how bright it is only its dangerous to skin and eyes

oscarruss wrote:


this could be your problem try using a different bulb

necromancer4 wrote:



i agree

right ok does anyone know if the fish will regain their colour and fins or am i fighting a lost cause?

good water quality = zero nitrite zero ammo and nitrate below 30ppm and in about 5-7 days your fish,s fins will regenerate fully and their colour will restore ...but you need the parameters to be as above or you ARE FIGHTING A LOSS CAUSE...............please post your parameters and get an ordinary fish bulb ..hagen aqua glow /interpet tropical or arcadia tropical will be fine....PLEASE POST YOUR PARAMETERS as fin disintergration are sighns of bad water as ammo and nitrite will burn the fins right off your fish:)

I'm going to get a test in a sec. the other bulb in the lid is a sun-glow 30watt is this ok or is it to bright

the 30w sunglo is perfect:)

Ok got the water tested bad news the UV light has killed all the bacteria So i have to start all over again:(

i cant imagine that happening .......what were the readings please