Hi Folks,

Thanks for your quick and useful replies.

I've just stripped out the tank today as described in my initial post, except removing the gravel - hoovered with siphon instead).

My water quality is: 28degreesC, 7.1 pH, 0 ammonia, 0 nitrite, 40ppm Nitrate, 10 dGH, 4dKH, 0.5 phosphate. My water quality has remained like this (approximately) since the tank was set up. Sometimes the Nitrate gets quite high, which is water change time, however I do use the green (nitrate) juwel filter, so it surprises me that the nitrates increase so much.

I bought the tank and all fish at the same store, I told them I was a complete novice and asked them to advise me with stocking my tank. They didn't tell me that the filtration may not be suitable, however there have been a few things I've since found out where they have ill advised me!

Should I consider a new powerhead?
If so, which power and brand would be best?

What kind of additional filter would I need?

Any advice about the treatments? Would it be safe to use these with the loaches?

Sorry to sound so clueless!
Thanks again for your help.