Difference between TDS, conductivity, kH and gH?

[MatsP]

I haven't got any idea what the water is like in Sydney, but certainly around here, I'd just take tap-water (hard as cement!) to raise the hardness of the water. However, if you have very soft water, that method doesn't work.

Using ANY salts, such as what RO-right that Racoll mentions, or bicarbonates or even regular aquarium salt would work - however, I'd probably recomment a less agressive salt than sodium chloride, perhaps caclcium chloride or some such.

--
Mats

[coelacanth]

Is there an agreed way of raising TDS in a tank after it has been put through a "wet season" without the nitrate increasing to much?
I don't have to worry about it as the TDS in my normal tap water is fairly high, but I have been asked the question by some friends that have very soft water from the tap.

Regards

During some lab experiments involving seasonally-spawning fsh spp., plain old Common Salt, Sodium Chloride, NaCl was used to effectively raise the conductivity to replicate the dry season without exposing the fish to poor water quality.

[PlecoCrazy]

I use two products from Aquarium Pharmaceuticals. The first one is called PH adjuster witch raises carbonate hardness (KH) and buffer water. The socond is called Electro-right and it adds "hydrominerals" back to the water. It says this raises the (GH) of the water. It claims that it is better than most commercial additives that only add sodium chloride and do not replenish the hydrominerals. The list of minerals it adds baCK is potassium, magnesium, chloride, sodium, calcium, sulfate, iron, vanadium, titanium, strontium, and manganese.

It gives direction on both just how much too add to get the carbonate hardness and the conductivity to right where you want it. This comes in liquid form which I like better than powder. Both products are specifically designed for use with RO water.

Link to their site

[AndrewC]

My tap water is very soft, out of the tap it reads; ph 7.8, kh1 & gh1, tds 80, after airiating and pre heating it reads; ph7, kh1 & gh1, tds 80.
But my tap water had very high phosphate readings (the deepest blue on the chart when i test it), which i have been told will affect a fishes health over time, the high phosphate reading must be because the water authoritys use a phosphate buffer to buffer my tap water, to stop the pipes corroding.
I know my tap water has a very low kh level, but my fish never showed any signs of stress, it is fry i can have trouble with and is the other reason i have invested in a RO Unit, at least i now know that it is not something in the tap water.

After running my water through the unit over the weekend and filling a 50G tub, the water read; ph 6.0, kh0 & gh0, tds 5.
I then added RO Right for trace elements, 1 teaspoon per 10 gallons for Discus (soft water), so i added 5 teaspoons to the tub, and it gave the water a reading of; ph6.8, kh1 & gh1, tds 85.

I wanted to raise the kh to three, to get the minimum buffering capacity in my water, so i added 3 teaspoons of bicarbonate of soda, and the water read; ph 7.8, kh3, gh1, tds 120.

Is this a very high ph reading for my water, the ph seems high to me for minimum buffer capacity in my water, i thought i would end up with a ph of around 7.2 ?
I have ordered Kent PH Stable, but thought i would be fine with bicarbonate of soda to raise the kh of my water, maybe PH Stable won't have as much affect on the PH as bicarbonate of soda has had ?
Or is there nothing wrong with a high ph, as my water is still reading quite soft ?

This topic has been interesting reading, as i have always thought you should keep softwater fish in softwater, or at most not too hard.