No disagreement on large water changes if the TDS or DOC change is not too great. My fish seem to love water changes too 
GH, KH, & TDS Clarification
- Thread starter sumtnfishy
- Start date
Yes I am sorry - So I have Fake Log - Fake Cave - Fake plants - Two pieces of driftwood and aquarium gravel. However as of last night my substrate is now fluorite underneath small small gravel. (WAY better for my geophagus and Cory cat) I am getting ready for plants. I just threw the fake decor back in for now.
No guys this is awesome!! I need to hear the different views on adding salt. No derailment here 
I prefer the larger and more frequent water changes. Keeping the tank as close as possible to tap conditions, if those conditions are desirable. Table salt is good for meds but not needed for any reason in regular doses. It works for some, but more as a placebo. Salt will affect the gill function. If you use it and claim great benefits, it is unfounded unless a similar tank of the same fish is kept from having it. IMO.
Tds is everything, from nitrogen waste products, hormones excreted by the fish, minerals, the metals from the pipe system, the "tea" from whatever has decomposed in the tank etc.
A test kit will not measure tds, but we can use nitrate levels in an unplanted tank to stand in for the total. It is only one variable in the soup but it usually works as a stand in.
Ph is in a fish tank is more complicated than a direct relationship of kh to ph. Part of the tds question has bearing on ph, since metabolic processes add organic acids and bases to the mix. As someone that has interest in CO2 injection in planted tanks I know that the measured ph after CO2 injection is the effect of CO2 ppm lowering the average of all the organic and non organic acids and bases. Simply put I can't calculate how much CO2 there is in the water by the difference between tap and tank measured ph because of the organic additions.
To get an accurate CO2 measure, I need to compare a sample of tank water gassed off to ambient levels with the current tank ph as adjusted by the CO2. One log ph difference in this case is the target of 30 ppm CO2. ( if the sample has a ph of 8.2 my tank target is 7.2, or if the sample is 7.3 my tank target is 6.3 with CO2)
That was perhaps not entirely applicable to the current discussion but as an example I hope it was educative.
A test kit will not measure tds, but we can use nitrate levels in an unplanted tank to stand in for the total. It is only one variable in the soup but it usually works as a stand in.
Ph is in a fish tank is more complicated than a direct relationship of kh to ph. Part of the tds question has bearing on ph, since metabolic processes add organic acids and bases to the mix. As someone that has interest in CO2 injection in planted tanks I know that the measured ph after CO2 injection is the effect of CO2 ppm lowering the average of all the organic and non organic acids and bases. Simply put I can't calculate how much CO2 there is in the water by the difference between tap and tank measured ph because of the organic additions.
To get an accurate CO2 measure, I need to compare a sample of tank water gassed off to ambient levels with the current tank ph as adjusted by the CO2. One log ph difference in this case is the target of 30 ppm CO2. ( if the sample has a ph of 8.2 my tank target is 7.2, or if the sample is 7.3 my tank target is 6.3 with CO2)
That was perhaps not entirely applicable to the current discussion but as an example I hope it was educative.
frank, I must respectfully disagree with both statements. I've been keeping fish since 1968, have done and do large-scale weekly partials and never prophylactically salt my tank(s).
I've kept most FW species from Discus to Tanganyikan cichlids and never salt the water unless a disease requires treatment.
To dispel a myth, just adding salt does not "soften" the water...it simply increases the TDS of the water. Ionic exchange softeners which use salt, exchange hard ions for soft ions and thereby "soften" the water, but since the exchange is at a 2:1 ratio, it also raises the TDS. The following article may prove useful...
https://www.theaquariumwiki.com/The_Salt_of_the_Earth
Mark
