i have a 170 litre tank in which i put a air freshner on top (stupid idea) the heat from the lights melted it and the liquid flowed into the tank at the time we had no fish in the tank i have done loads of water changes even drained all the water and started again but every time we add fish they die after about 2 days sometimes over night does anyone have any ideas? Im using an eheim 2234 external filter and a fluval 3 internal filter

empty the tank completly of all ornaments gravel everything.....then drain it out completely wipe it all dry with towels untill all the glass is dry!!!!!!! put about a kilo of salt in a plastic bowl in the bottom of the tank close the glass sliders and the lid and leave it for 4 days .............the salt in the bowl will work as a dehumidifier and draw all remaining moisture in the tank and in the air in the tank.int the bowl so any remaining trace chemicals from the air freshener will be transfered to the bowl of salt and can then be removed from the tank EASILY.....any fish you have will have to be rehoused (see post on .bought new tank but fish come too)for instructions on how to keep you fish untill you sort your tank....but DO NOT USE ANY WATER OR FILTER FROM YOUR OLD TANK you will just have to take a chance on uncycled water if you HAVE NO OTHER OPTION

then after you have removed the salt follow OFL,s instructions on the homepage on HOW TO CYCLE A TANK make sure the water parameters are fine BUY A TEST KIT not the test strips...............and you will keep fish no probs as long as you carry out regular water changes keep a check on parameters and DONT FEED YOUR FISH ANY MORE AIRFRESHENERS............ hope this helps let us know how you get on ....oh and the salt in the bowl will become wet on its own this shows you its working.

disgard any filter media and replace with new....and run your filters in a bucket with new media for a week while you are sorting your tank so they can start to cycle by the time you are ready to put them back in they will have almost cycled the new media .....WASH THEM OUT BEFORE YOU PUT THE NEW MEDIA IN THEM THO ..........bobs your uncle,fannys your aunt....

verification:
after the freshener incident, how long did
you cycle the tank before putting new fishes?

have you replaced all filtering media after the accident?

cycling the tank will normally take 3 weeks before being
ready to accommodate occupant/s. as biggamehunter said,
please go to the section "tank cycle" to fully understand
why you had such a dying fish whenever you put them in
your tank.

its been 2/3 months since the air freshner. will i have to replace gravel or can i clean in any way?

as i said in my post EVERYTHING must go .......

does that also mean the pipes for the filter. how do i clean the bogwood

run the filter as i said in the above post with old pipes and you can boil the bogwood with salt water ....hope this helps

i forgot to mention when in the tank the plants started dieing almost straight away but since i put them in a tank on their own they have started turning green again

that tells you you need to follow the instructions given by forum members to sucessfully reuse your tank the plants are NATURES TEST KIT!!!!!!!!!!and they say GET ME OUT OF THIS TANK!!!!!!!!!

Thats what i thought well i have done as you said and i am replacing everything i will keep you posted over the coming days as to what happens

make sure to put the salt bowl in for a while and FOLLOW EXACT instructions ..including the tank cycling and let us know how you get on give us an update every few days please ......GOOD LUCK wish you the greatest of success;)