LostInFish
Aquarium Advice FINatic
I have been trying to figure out what is the right TDS ppm and it seems even my very reputable LFS couldn't answer that. But what my search for answers has found was that certain fish have certain needs like Discus need a really low TDS but not to low because u still need minerals and things in the water for your fish to be healthy. In the other hand african cichlids have a higher tolerance and actually need TDS in the tank To function there salt/water intake through the gills and kidneys. But again if it's to high it will cause problems. So in my estimate between 300-500ppm for Africans and like 50-300 for soft water fish depending on the fish of course. These are just my opinions from what I have read and talked to people about along with personal experience. I have read that lake Malawi was like 150-250ppm TDS but I find that hard to believe with the Gh and Kh being so high on top of other minerals and organic matter in the water. One other site I read had a TDS 600ppm for Tanganyika but that's all here say. Right now my tank is at 415 TDS with ph 8.2-8.4 gh12 kh12 and my fish seem to be doing good so far. My tanks been established about 8 months I just recently changed my water parameters from 7.6 gh10kh5 to 8.4 gh12 kh12 and it's been 1 day so far fish look good seem to be eating very well. The only thing I noticed that was different was my synodontis Petricola catfish were playing in the open water more. Before I hardly ever seen them.