Hi Wilder,
Thanks for the reply.
165L Tank
4 fish at present - 2x Angels, 2 x Silver Dollars, 1 x Yellow Gourami
Ammonia 0, nitrite 0, nitrate 10-12, ph 7
Just changed 1/3 water and new carbon.
Hopefully they go well.
I'm not sure how old the Angel's are, because I bought them full grown...