tropical fish tank

[yukka]

could any one please tell me why the pepples in my fish tank have turned nearly black, i clean it out quite often i have got about 12 fish in it. cheers thanks a lot.

[robotics]

Is it a freshwater tank or a marine tank, how often to you replace the pebbles?

Joanne
mygermanshepherd.co.uk

[robotics]

Another one, how long have you had the tank?

joanne
mygermanshepherd.co.uk

[heathfield]

With an immersion heater, the water is warmed, but the base of the gravel bed can remain at room temperature. This leads to a lack of water circulation in the gravel, and results in anaerobic conditions that produce the black mould.
A heater element fitted under the gravel will produce circulation of the water through the whole of the tank, and prevent the mould. Otherwise, it's a case ofremoval and cleaning.

[yukka]

joanne, i have had the tank and contents for about 9months, it is fresh water and i change the water regularly, or part of. and i have never changed the pebbles. i also have live plants. thanks for asking Raymond.

[yukka]

hello heathfield, cheers for the reply, i did not know there was a heater that went under the gravel, other wise i would have to change the whole set up and that would mean starting from scratch but still if you have to sobeit. thanks a lot mate for that. cheers Raymond.