No - "Activated Carbon is also a catalyst that converts free chlorine (Hypochlorite ) to chloride which is easily adsorbed"I think the carbon works as a catalyst when removing chlorine, so it should be effective in this respect indefinitely. Am I wrong?
After changing the basis water from rain to RO, I observed that all my crystal shrimps have died. Cherry shrimps are also not very happy from what I see.
Yes, it's likely the same parameters I have in my tank. The problem is that 1) I don't need that high PH; 2) I don't want all PO4 to be absorbed and excluded from the buffering system. And I've never seen such a behaviour with old Tropica soil. Probably it wasn't old enough though. I think I need to use RO only during water changes and add some CaCl2 for GH raise.I wouldn't expect anything else.
You could hardly prevent it from happening. Phosphates readily adsorb to metal oxides, organic matter, clays.I don't want all PO4 to be absorbed and excluded from the buffering system.
Yes, I'm aware of this process. In fact, with hard water and soil you can even reach green drop-checker due to extra protonation and absorbtion of the Ca/Mg cations (leaving HCO3- as H2CO3 basically). But it seems that my soil has no protons left, but it has some Mg/Ca and I really don't know the exact cations balance and so on. Indeed, it could be that soil has absorbed too much Cu(2+) somehow and it got suddenly emitted to water... Yes, there are free EDTA and other free chelators in that water but I'm still not convinced.Then you can pack it under the name ADA Amazonia and when it comes to hard and alkaline water, it will bind metal cations and release protons instead.
Well, certainly a possibility.it could be that soil has absorbed too much Cu(2+) somehow
RO water cannot have more copper than tap water apparently.
Maybe rainwater -> RO change is negligible, and the culprit was the temperature rise (I normally keep this tank at around 19-20 degrees, but it got heated to 27 degrees during the recent heat). Perhaps, that temperature change could have caused some structural changes in the soil. Does it look possible?What intrigues me is that both rainwater and RO water should be of low ionic strength, so replacing one with another should not make much of a change. Still, you lost some shrimps, and water pH behaves differently. I don't get it.
Good idea, I think. Temperature may influence many reactions. The problem is that the soil is a blend of myriads of substances, so one never knows for sure...Does it look possible?
Maybe, as with the conjunction of the raised PH it might be really bad. As I've said, I add half of my N as urea, that actually hydrolises to NH4+ in aqueous solution with time (and my hand made fertiliser was quite old to have all urea N as NH4 N). Normally, it is not a problem as plants absorb NH4 quickly, but this process is also not persistent: e.g. it heavily depends on lighting. So maybe higher temperature, higher PH, higher ammonia, less oxygen (due to temperature rise). That wasn't that bad for fish but crystal shrimps seem to be much more sensitive...What if the released cations were ammonium?