Plan of attack for the pool filter maintenance

Once you have checked the filter, if it is choc-a-bloc with goo then anything could be happening to the water quality of the pool, either as a result of the goo or it could be the cause of it. If you have more than one filter or there are several chambers to your system, just close one at a time and spread the servicing over a two-week (preferably longer) period.

But before we get into the grimy details of full filter and ancillary servicing, you may have a situation where the quality of the pond water needs to be attended to immediately. This process can be going on whilst you attend to the filter. If you forgot to address the problem straight away and you discovered high ammonia levels in the water after you cleaned out the filter then this what to do:

  • Follow the previously mentioned emergency remedy with a partial water change of between 20% and 30%.

  • Repeat this daily until the levels drop to a level that it does not register, adding a water conditioner each time.

  • If the temperature of the water is rising to above 5C after being well below for some time or if the filter system is very new, add a filter bacteria additive to kick start the filter into action. Repeat this every evening on a daily basis for about 10 days.

  • Refrain from feeding the fish until the temperature reaches 7C and then only feed lightly. Specific feeds for this time of year, traditionally high in wheat-germ, are recommended. Feed ordinary low protein food only when it seems temperatures have stabilized above 10C. Above 15c high protein foods can be used.

If nitrite levels are high:

  • Carry out a water change of 30% or 40%. Alternatively add pond salt at 3-6gms per litre. This will certainly help the fish to maintain their mucous coat, which is their only barrier to many pests and diseases. If you have been persuaded to use zeolite in your filter do not add salt to the pool.

If the pH is high try to find the cause:

  • If it excessively alkaline tap water and you are intent on some serious koi keeping then a water softening system might be the only solution for your peace of mind. Otherwise there are chemical treatments to bring down the pH temporarily or you could use rainwater to top up your system.

  • Ensure there is no runoff over limestone or cement into the pool, seal with G4 or treat with silglaze concrete ornaments and exposed cement mortar.

  • Water running over limestone will affect the pH of the water quite radically. At the very least it will certainly slow down the process of becoming a stable wildlife habitat. This Brian Aughtons Hansel and Gretal garden at Tatton Park Flower Show 2004.)