Normally when you begin to experience frequent sudden deaths, the course of actions you can take is to test parameters, usually something is off and you may or may not find the answer with the results. Considering there are multiple possible issues causing the deaths, the current test kit you have in your arsenal may not be able to test for everything CO2, NO2, NO3, PO4, NH3, pH, Fe, GH, KH etc.
The initial reaction for me personally is to reduce the harm present, so dilution in most cases is the superior action to take to reach a solution. I normally go for 20-30% water-change in the hopes to correct whatever is creating problems, but 50-80% water-changes are not out of the question with slow drip feeds back in over the course of several hours to ensure minimal parameter shifts.
A simple way of putting it is, say the nitrate (NO3) is 20ppm, you want to cut that outcome by half, so a 50% water-change may be required to reduce and help the tank return to normal readings. Sometimes the threat may be hidden, speculation can revolve around different harmful bacteria outcompeting the positive ones present, perhaps due to temperature, changes in feeding, shifts in population sizes from a cull. I personally have found water changes to be the quickest way to re-stabilise the colonies.
Hence, dilution is the solution. Hope this was helpful, if you have further questions feel free to plop on over to our Facebook Group – Shrimp Enthusiasts Australia.
