sera guide - Healthy pond fish

54 Do not use during a treatment Active carbon must not be used during a treatment as it binds medicinal agents and thus reduces or even cancels the efficacy of the treatment. Some of the active treat- ment agents can also be broken down or bound by a particularly large and active bio- filter and plenty of bottom gravel. It may therefore be advisable in single cases to slightly (e.g. to 1.5 times as much) increase the treatment dosage as to maintain full efficacy under such special conditions. Using water conditioners, especially ones with finely ground rock powder, immedi- ately before (within 1 – 2 days) or during a treatment may also lead to slightly dimin- ished efficacy due to binding the agents. Therefore it is best not to use water condi- tioners during this limited period. Their use, however, is even more reasonable after the treatment (see page 56, “Concluding the treatment”). UV-C lamps for water disinfection should in any case be switched off during the treat- ment. The high energy light destroys many active agents. Filtration during the treatment Information for use leaflets often recom- mend removing biological filters from the water circuit during the treatment. This is a precautionary measure, as some treatments may also harm filter bacteria and – as stated above – very active filters might reduce the efficacy of the treatment. However, discon- necting the filter is usually laborious and inconvenient. You would need to spread the filter material, e.g. in a tub with pond water, or ideally operate the filter connected to a separate tank especially in case of long last- ing treatments. Rot processes might occur if water does not flow through the filter material for too long (it can get critical after half an hour), which possibly leads to anaer- obic conditions. This leads to the formation of, among others, highly toxic hydrogen sul- fide that may poison the pond inhabitants if the filter is put back into operation again without being cleaned. Pathogens may also be present within the filter itself, which might cause a new infection after the filter has been connected again, which is another disadvantage. A stable, biologically well established filter with suitable filter materials 10 General recommendations for application