Does lava rock and silica sand increase kH and TDS?
- Thread starter boyohboy
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cool thanks.
But then comes another question:
I have about 60G of water, and I've been adding/switching to R/O water slowly every day. I've replaced around 25G of R/O water to the 60G of tank.
My tap water is about 190-200 TDS
My 60G water is at 210TDS still, after adding all those R/O water!?
So I dont' understand what caused that. I have lava rock and silica sand in it, but I too remember I've checked somewhere they shouldn't affect kH and TDS. So what's the cause?
But then comes another question:
I have about 60G of water, and I've been adding/switching to R/O water slowly every day. I've replaced around 25G of R/O water to the 60G of tank.
My tap water is about 190-200 TDS
My 60G water is at 210TDS still, after adding all those R/O water!?
So I dont' understand what caused that. I have lava rock and silica sand in it, but I too remember I've checked somewhere they shouldn't affect kH and TDS. So what's the cause?
Describe everything in your tank, include as much detail as possible.
Fish food and wastes can increase TDS, but I can't think of a route for them to increase KH offhand. I'll have to think on it some more...
Fish food and wastes can increase TDS, but I can't think of a route for them to increase KH offhand. I'll have to think on it some more...
well, there's only lava rock and silica sand in the tanks, a few small plant of java ferns and anubias nana. And only a dozen young apisto in the whole 60G of water. Haven't really overfeed or anywhere close to that.
I dont' have a kH kit yet, but will get one. Maybe the kH does go down but somehow the TDS (non-carbanate stuffs) remain high for whatever reason? but where the stuffs come from?!
I dont' have a kH kit yet, but will get one. Maybe the kH does go down but somehow the TDS (non-carbanate stuffs) remain high for whatever reason? but where the stuffs come from?!
The R/O unit is fine, the output water has TDS of 000-001. And I'm usting the same TDS meter from the R/O unit to test the tank water too, so can't be a problem with the TDS meter either.
Your TDS meter measures conductivity, right? Or resistance, six of one...
Based on the scale we're talking here, it doesn't look like a TDS of 200 is all that high.
While CO2 equilibrium doesn't affect KH, it will likely affect TDS. RTR can correct me on this if I'm wrong.
When CO2 equilibrates with water it produces bicarbonate and carbonate, along with a charge equivalent of H+, hence no change to KH. However, I think that the definition of TDS ignores H+, measuring only the carbonate species. Just a guess though...
Based on the scale we're talking here, it doesn't look like a TDS of 200 is all that high.
While CO2 equilibrium doesn't affect KH, it will likely affect TDS. RTR can correct me on this if I'm wrong.
When CO2 equilibrates with water it produces bicarbonate and carbonate, along with a charge equivalent of H+, hence no change to KH. However, I think that the definition of TDS ignores H+, measuring only the carbonate species. Just a guess though...
The first question is whether or not your silica sand really is that. Make a cleaned sample of the sand (about 1/2 glass) with multiple RO rinses, then leave it is a glass bowl with its own volume again of RO, cover w/glass or waxed paper, and monitor daily for TDS. Much sand on the market is not pure silica. Southdown being one of the better examples. A good acid test (muriatic or such -dilute HCl, not table vinegar) is easier, but not quantitative.
Repeat for the lava rock - I had one batch which released heavy metals - I should have known better, it was quite dense stuff.
The percentage of dissoved CO2 present as carbonate/bicarbonte is quite small, I have it somewhere, but not handy. It is low enough that except well past biologically viable levels of CO2, I doubt that you would find it significantly detectable on TDS - detectable with good meters, yes, significant, doubtful.
Repeat for the lava rock - I had one batch which released heavy metals - I should have known better, it was quite dense stuff.
The percentage of dissoved CO2 present as carbonate/bicarbonte is quite small, I have it somewhere, but not handy. It is low enough that except well past biologically viable levels of CO2, I doubt that you would find it significantly detectable on TDS - detectable with good meters, yes, significant, doubtful.
Guess we'll see in a day or two.