Random Thoughts

Gravel:
The gravel actually looks quite good now, I had my doubts but now its in the tank and settled after a few days it looks nice and bright with a good mixture of colours, am glad i choose it and not the standard yellow or blue gravel  packets in pet shops.

Heating:

I had planned on having the heater within the filter unit as its designed to be but while i was testing things a few days ago i noticed i was struggling to get a temp over 25c, despite the heater thermostat nearly set at 30c so it looked like the 200w heater was not going to be suitable. I even tried the heater dangling in the middle of the tank just to see what would happen but it only got to about 26c and that was it.

It was then i decided that the heater was not strong enough for my tank (maybe faulty too), so got myself a 300w one and it seems to be working ok, just a pity its too long to fit in the filter unit, so its attached to the back of the tank.

Filters:

One thing that really puzzles me is the filter media. I just cannot fathom how it works.

The Juwel Compact sponges just look like pieces of plastic kind of material with holes in them, I just cant figure out how bacteria can grow on it?, especially the bottom blue one.

The water enters from the top and then down through the filters, there is a hole half way down just at the bottom of the green sponge and it gets sucked up to the pump, but then there is a hole at the bottom of the unit where the fine blue sponge is, makes me wonder how the water would get that far down as it would get sucked up through the upper hole I am sure.