TDS

[abaigael04]

Just got my TDS meter. I am doing my WC in an hour or so... but I tested it just now. The TDS in my loach tank was 303. In my 10 gal. with a 2" fish it was 285 or something like that. Is that OK for Clowns? Or a bit on the high side. Should I test my tap (do I need to let it sit overnight, if I do? Since I suspect it is my tap making it so high) My nitrates are always very low - 5 or less. (none of my fish are big, and so I have a pretty low bioload for *now* and only do 1 WC a week (20-25%)). My water is medium hard, too.
Thanks!

[Diana]

My tap and tanks are mostly running in that range (upper 200s to mid 300s) and the fish are fine, including Discus, Angels and others that like softer water.

The tap water does not have to sit out to be tested, but you might test it right out of the tap, then let the tap run for a minute or two. If the second test is about the same, no problem. If the second test is significantly lower then it suggests that water sitting in your pipes is picking up some minerals.

[chefkeith]

Congrats. A TDS meter helped me figure out many of the mistakes that I was making.

Subtracting the aquarium water reading from the tap water reading will give you an idea of how much stuff with conductivity has accumulated in the tank.

When I got my TDS meter I couldn't believe how much my TDS fluctuated during and after water changes. I was injecting CO2, adding fertilizers, using crushed coral in a refugium, had rocks that were leaching, adding water change water too quickly, and had water pumps that weren't circulating the water quickly enough throughout my multi-tank system. It was perfect storm to cause osmotic stress on the fish.

Avoiding quick TDS changes is one of the best things I've done to help keep my fish healthy.

[abaigael04]

My tank AFTER WC was still at 303. Tap is 211. Even after running for a few minutes. Is that OK? Or how would I fix that? More WCs? The only this I add to my tank is flourish. I do about half doses.

[chefkeith]

Flourish will add to the TDS. Not sure you need to fix anything. Just keep the TDS steady. If you make TDS changes, make them small and slow.