Advice And Reassurance For A Newbie?

Hi everyone! I'm new to fishkeeping and  these forums and was hoping for some advice.  I recently bought a 120l fishpod, set it up with substrate, gravel a few plants and ornaments. I switched on the filter and heater, left it to settle for a few days then added ammonia to begin the fishless cycle.  It is now day 10 since the addition of ammonia and there has been no change in the water tests, ammonia is at 4ppm, nitrite is 0, and pH is 7.5. The heater is currently set to 30 deg C.

Now for my questions! First of all, 9 days after setting up the aquarium, i noticed that the water movement from the filter had visibly decreased, I took it apart and cleaned it (in tank water) and it seemed to return to full function. It is now 4 days after cleaning and the function seems to have dropped again. Is this normal, or is the filter struggling to cope with the size of the tank?

appearance wise, the water is slightly murky, and a fluff-like substance has started to accumulate on the plants and ornaments, is this normal?

Also, there seems to be an oil-like substance on the surface of the water, everything was washed prior to set up, and the only things that were added to the water is tapsafe and some filter start (came with the tank) which i added in the first few days. any ideas what this could be?

Finally, is it normal for no changes to water tests in 10 days since the ammonia was added?

I'm sorry to bombard you all with questions, but I want to make sure I don't make any silly mistakes!
Thanks for reading 

My ammonia dropped on day 13 (counting the day I started as day 1) and was zero on day 14. But I was using just 1ppm ammonia. Your higher level shouldn't make it longer to see the first drop, but it may well take longer to get all the way down to zero.
But just because mine dropped on day 13 it doesn't mean yours will, unfortunately, but 2 weeks does seem to the most common.

Once it does drop to zero, can I suggest adding more ammonia only to 1ppm. The more ammonia you add, the more nitrite is made and eventually more nitrate. It is now becoming accepted that high levels of these two can inhibit the nitrite eating bacteria and that the better way to fishless cycle is by starting with lower amounts of ammonia and increase it once the nitrite eaters are growing.


Like Steve, I don't know why your filter flow keeps dropping. What is inside the filter? Some types of media do clog more quickly, but it's fish waste, uneaten food and bits of dead plant that usually do the clogging. During a fishless cycle, there aren't any of those in the tank.

It could be the fine pad, they do clog easily - but you don't have anything to clog it 

If you do decide to get an external, now is the time to do it.
You could either run both, since you are right at the start of the cycle you still have a lot of bacteria to grow so both filters would cycle side by side. You would end up with both types of bacteria in each filter, the amount in each would be in proportion to the amount of media in each. Since externals have a lot more media than internals, the majority of the bacteria would be in the external.
Or if you wanted to run just the external long term, either start again from scratch (you'd lose about 2 weeks) or carefully cut up the media from the internal and bury it in the media baskets of an external. that way you should still keep most of any bacteria you have grown so far - provided you are gentle and don't let the media dry out.
The problem with having to clean the media so often is that you could well be dislodging some bacteria. They grow in the biofilm and that takes a while to become firmly attached.