High Microseimens measurement in the aquarium, Confused.

[foxbat426]

Hi, My question has to do with the water I know I'm putting into my tank, Vs. the measurements I'm seeing in the tank. I have very hard water and adjust the Microseimens to about 160 with a combo of RO and Tap. I know what it is Im doing water changes with, but when i measure the uS directly in the tank im seeing nearly 500 600 uS measurements! my heckels and Altums are doing fine, but this has me confused. Im sure my gravel for the most part is inert, im using black diamond sand, and I have no rocks or any high calcium-based items in the tank. in fact the tanks with just sponge filters are giving very high readings. When i put a bit of the black diamond sand in RO water im not seeing any jump in PPM or uS's. any ideas?? thanks for viewing. Good to be back on SD!! John in Fla.

[jwcarlson]

Are you adding any dechlorination chemicals between taking readings?

[jimg]

my thoughts would be on the amount of water your changing meaning how much older water is left in the tank. i for a time based my water change amount with my heckles and altums on how high the uS would go i too used ro and tap mix to get the correct uS.

[LizStreithorst]

Is your water going through a water softener?

[foxbat426]

i do add a small amount of prime to the RO tap mix, just in case. Im sure this is contributing to the count.

[foxbat426]

yes i think thats what is going on Jim. I did a 50% water change today and the TDS dropped to about 200ppm. Im adjusting the water mix at this time to about 150 uS's which is about double the TDS measurement. So it is coming down. Im sure its probably just other tings like Nitrate, Water conditioner, fish waste etc, that im seeing and not hardness. I'm sort of understandiing it better now and the measurement is probably a good one to show when a water change is warranted.

[foxbat426]

Hi Liz, Thanks for the response. No I do not. i'm sure now that i probably need to up the water changes.