Holy crap! I have been using 170ppm TDS water!

[daniella3d]

yike! This is bad and a good reason to use RODI water. I know someone who lost about 30 large discus fish to some chimical in tap water many years ago. It does happen.

I tested my tap water and the TDS is 120, but there is no trace of nitrates or phosphates in it so I am guessing that it would not fuel algae, but I still use RO water.

Originally Posted by Aquattro

Usually when I talk about water contamination, I'm referring to a year I lived in Kelowna and the entire drinking water distribution circuit was shut down due to toxins in the water. If someone had done a water change that day before the emergency was declared, I'd guess they'd lose their whole tank. It doesn't happen often, but it does happen. The Kelowna sewage treatment plant discharges directly into the lake, and while the water coming out is top quality, if there were an accident, the lake would be contaminated. The cost of RO is small compared to replacing everything in the tank