Something strange going on. Extremely high TDS in rock "curing" water

cvrle1 · 03/06/2020, 04:10 PM

I am stumped, and can use your help with this one. I have extremely high TDS from water that is sitting in the rock bucket. High as in 880 ppm

I calibrated my Milwaukee TDS meter with proper calibrating solution to 800ppm
Tap water, I have TDS reading of 12-18 ppm (Inline TDS meter on the RODI is showing 12, Milwaukee TDS meter is showing 18)
Clean water coming out of RODI is showing 0 on inline and 2 on Milwaukee (milwaykee has +- 10ppm accuracy, so this is fine I think)

I filled up bucket with dead rock that I bleached several months ago (using bleach and tap water) with RODI water and let it be for 2 or so weeks (no salt or anything else, just RODI water). I have powerheads in there to move water around. I just took a sample to get TDS reading and got 880ppm with Milwaukee

ops:

For rock, I bleached it all (about 120#) in bleach and water solution for a week, let it dry out in the sun for a week and then put it back into the bucket. I washed bucket out with hose and dried it out as well before I put rock back in. Rock was sitting dry in that same bucket for 3-4 months. Before I filled it up with RODI water there was no bleach smell.

Could bleach residue somewhere cause readings this whack? Something else? No idea what happened and why I have way worse TDS reading than tap water.
Thanks for the help

cvrle1 · 03/06/2020, 04:40 PM

Looking into this more, and it looks like it is expected. Apparently adding rock, no matter how clean will add to the TDS reading. I just didnt expect it to be this bloody high. 880ppm... jeebus.

Sk8r · 03/07/2020, 02:03 PM

Rock is minerals. When they dissolve in water, they add to the Total Dissolved Solids.

billdogg · 03/10/2020, 02:26 PM

Quote:

Originally Posted by Sk8r

Rock is minerals. When they dissolve in water, they add to the Total Dissolved Solids.

^^^Sk8r FTW!!!^^^

FWIW - ANYTHING you add to the 0 TDS water will increase the TDS (unless it's more 0 TDS water) - even just using an airstone to keep it aerated will increase the TDS due to whatever impurities happen to be in the air itself.

cvrle1 · 03/10/2020, 04:09 PM

Thanks both. Clearly I wasnt aware of this, but it makes sense for sure. I almost gave myself a heart attack when I saw 880ppm lol.

tomreefer · 03/10/2020, 06:48 PM

I would make 100% sure no chlorine by testing it with those strips to be safe.

03/06/2020, 04:10 PM	#1
cvrle1 Registered Member Join Date: Nov 2000 Location: Surrey, BC Posts: 454	Something strange going on. Extremely high TDS in rock "curing" water I am stumped, and can use your help with this one. I have extremely high TDS from water that is sitting in the rock bucket. High as in 880 ppm I calibrated my Milwaukee TDS meter with proper calibrating solution to 800ppm Tap water, I have TDS reading of 12-18 ppm (Inline TDS meter on the RODI is showing 12, Milwaukee TDS meter is showing 18) Clean water coming out of RODI is showing 0 on inline and 2 on Milwaukee (milwaykee has +- 10ppm accuracy, so this is fine I think) I filled up bucket with dead rock that I bleached several months ago (using bleach and tap water) with RODI water and let it be for 2 or so weeks (no salt or anything else, just RODI water). I have powerheads in there to move water around. I just took a sample to get TDS reading and got 880ppm with Milwaukee ops: For rock, I bleached it all (about 120#) in bleach and water solution for a week, let it dry out in the sun for a week and then put it back into the bucket. I washed bucket out with hose and dried it out as well before I put rock back in. Rock was sitting dry in that same bucket for 3-4 months. Before I filled it up with RODI water there was no bleach smell. Could bleach residue somewhere cause readings this whack? Something else? No idea what happened and why I have way worse TDS reading than tap water. Thanks for the help

03/07/2020, 02:03 PM	#3
Sk8r RC Mod Join Date: Feb 2006 Location: Spokane WA Posts: 34,628 Blog Entries: 55	Rock is minerals. When they dissolve in water, they add to the Total Dissolved Solids. __________________ Sk8r Salinity 1.024-6; alkalinity 8.3-9.3 on KH scale; calcium 420; magnesium 1300, temp 78-80, nitrate .2. Ammonia 0. No filters: lps tank. Alk and cal won't rise if mg is low. Current Tank Info: 105g AquaVim wedge, yellow tang, sailfin blenny,royal gramma, ocellaris clown pair, yellow watchman, 100 microceriths, 25 tiny hermits, a 4" conch, 1" nassarius, recovering from 2 year hiatus with daily water change of 10%.

03/06/2020, 04:40 PM	#2
cvrle1 Registered Member Join Date: Nov 2000 Location: Surrey, BC Posts: 454	Looking into this more, and it looks like it is expected. Apparently adding rock, no matter how clean will add to the TDS reading. I just didnt expect it to be this bloody high. 880ppm... jeebus.

03/10/2020, 04:09 PM	#5
cvrle1 Registered Member Join Date: Nov 2000 Location: Surrey, BC Posts: 454	Thanks both. Clearly I wasnt aware of this, but it makes sense for sure. I almost gave myself a heart attack when I saw 880ppm lol.

03/10/2020, 06:48 PM	#6
tomreefer Registered Member Join Date: Jan 2014 Posts: 767	I would make 100% sure no chlorine by testing it with those strips to be safe.