[Pavel Chaloupka]

Yes, given that you don’t need to fight with any kind of alkalinity, the amount of acid needed to drop the pH down is very small and even strong anorganic acids that dissociate to high extend do not raise the conductivity much. I do not use it with Paros but I do with other fish that can’t stand that many humic substances with the same results. Sulphuric acid will raise the conductivity about the same,around 5 µS one drop in 5 liters. For Paros I use alder cones extract as I work with lower conductivity water at the start and alder cones extract is able to raise it a little. I soak big handfull of cones in 1 liter of RO water for about a day, this way I get extract that has something like 60 µS and I use 1/2 liter of it for every 5 liters of water. For having enough humic substances I sometimes use this: http://www.amagro.com/aquaristic.html as it is a pure humic/fulvo acids extract prepared from waste material after production of paper. This way no peat is used and you do not support destruction of peat bogs + it is free of heavy metals and other harmfull substances that acumulate in peat. The dosage is 2.5 ml/100 liters so one bottle lasts you for ages.