We both are right. The fishes can take Calcium from water, also the fry grows up more rapidly in soft water than in hard water (despite the ratio of shorted gill plates fish). Taking Amazon river as sample, the wild discus should be "shorted gill pates" but they arent. SO they must to take calcium from the feed. Aquatic or terrestrial Arthropods species have a high content of calcium, but black worms are not Arthropods. Also the animals need Phosphorous to build up its skeleton properly. The problem of the Calcium in feed, it is not well metabolized/absorbed as Calcium ion, it should be binded to organic molecules. The Phosphorous is available everywhere and easy to metabolize.
I Agree but H2O2 is beneficial for the nitrifying bateria in right dose.
Quite possibly true as well, although it takes quite of bit of PP to kill off a mature sponge filter. The filter can usually "bounce back" with little or no issues, and is a little less suspectable to total die off then other filters like a HOB, but it can happen. If you have low PH levels (often the case with straight RO) it can effect the rate of miosis and retard how fast the beneficial bacteria can bounce back. If your neutralizing the PP with hydrogen peroxide you have to be aware that H202 can nuke a filter too.
Yes, it is true, the fishes seem to breath easy if you add some salt in the water, but in fact they are suffering acidosis and you will end up with unexpected mortality and weird behavior. Raising up temperature and using salt is a killer coctel. Salt MUST to be used in presence of O2, ie: inside sealed bags.
I loved this part (ie: I agree). Several times I have argued with others regarding the use of salt when treating for gill/breathing issues. The popular misconception is that since salt lowers the breathing rate of fish, it is therefore making thier breathing easier. This is simply not the case. By using this misconception I could also summise that clove oil must also aid in breathing, as it too lowers the resperation rate, and we all know that isn't true.
Rick