Operation of the AQUA-MARE Aerobic MSTS
The most important part of the process is to provide an adequate volume of dissolved oxygen to the aerobic bacteria in the aeration tank, which in turn will provide a good level of activated sludge at the bottom of the tank, an efficient de-nitrification process, and a clear liquor at the top of the tank suitable for de-canting and further disinfection.
Your AQUA-MARE Aerobic Marine Sewage Treatment System (MSTS) was tested and preset in the factory before delivery. However, if your system does require adjustment, is a simple task to reset the timers that control the three phases of the process.
A. Early Models
In early models of the AQUA-MARE 400 (for example), the amount of time allocated to each phase is controlled by manually adjusting several potentiometers (timer pots) located inside of the control module. These potentiometers are clearly marked as to their function. The default settings are as follows:
Blower On: 60 minutes
Blower Off: 60 minutes
Decant: 20 minutes*
Sludge No. 1: 5 minutes*
Sludge No. 2: 0 minutes*
Note: The processes marked with an * occur within the 60 minutes of the second phase – Blower Off.
The above example settings will provide a complete cycle of the system every two (2) hours, resulting in treated fluid being discharged once every two hours.
If the storage volume available within the aeration tank is insufficient for some reason (e.g. more-frequent-than-expected toilet use), the operator may need to reduce the process time e.g.:
Blower On: 30 minutes
Blower Off: 30 minutes
Decant: 15 minutes*
Sludge No. 1: 5 minutes*
Sludge No. 2: 0 minutes*
Using the same approach as before, the above settings will reduce the complete cycle time to one (1) hour, allowing two discharges within a two (2) hour period.
Please keep in mind that your MSTS is designed to provide a high-quality treated effluent for release back into the environment. NWS manufacture various sized systems for various applications and usage rates. As a general rule, we prefer to estimate tank size to usage at a 2:1 ratio; simply put if your aeration tank contains a maximum of 1200 litres and your system is operating as per manufacturer’s instructions, your MSTS will readily process 400 litres of toilet waste per day with some reserve capacity. The number of flushes that a system will handle can therefore be calculated by dividing the process volume (i.e. not the tank volume) by the number of litres used per flush.
Please note that if you overload your system during peak periods e.g. process 1000 litres per day through a system designed to process 500 litres per day with a maximum tank capacity of 1000 litres, the quality of the treated effluent that is discharged overboard may not meet the legislative requirements.
B. Later Models
Later models of the AQUA-MARE MSTS are controlled by digital ‘read-out' displays and touch-pad control panels. The main differences between the earlier and later versions of the AQUA-MARE are:
(a) Digital ‘read-out' display and touch-pad control panel;
(b) The run time of the discharge pump is set from the time the float switch turns off. This allows the float switch to normally remain above the chlorinated solution extending the operational life of this float switch, and
(c) The discharge pump is positioned outside of the tank (instead of a submersible pump) again providing increased service life. Once primed, a foot valve fitted to the base of the in-tank pick-up pipe will maintain the prime.
The timer settings of this later system are adjusted by selecting the required mode using the touch pad and electronic display, scrolling up or down to get the desired value, and then pressing ‘enter'. The ‘mode' selections available are:
Air On -> Air Off -> Auto -> Decant
The range of values available for selection are:
Air On: 0 - 225 minutes
Air Off: 0 - 225 minutes
Auto: 0 - 225 seconds
Decant: 0 - 225 minutes
C. New Models (2007 onwards)
Coming soon… once I finish testing the new electronics.....
D. Alarms
Your Aqua Mare is fitted with an emergency high-level switch in the aeration tank. If activated, the system will automatically change to ‘Air Off' or Settling mode and then commence the Decanting cycle at the end of the Settling cycle.
In earlier models, a remote alarm (which can be located near the helm) is provided to inform you of this situation if it was to occur. Please ensure that the alarm is connected into the system, along with the ‘Grinder Tank High Level' and ‘Grinder Pump Water Intrusion' alarm if a Grinder Tank is fitted.
In the newer models, all high level alarms (except the water intrusion alarm provided on 240 volt grinder pumps) are integrated into the remote Control Panel.
E. Chlorination
Chlorine tablets or liquid chlorine solution are the normal forms of providing disinfection for your system. Both the 200gram Chlorine tablets and the liquid chlorine solution are consumable items and should be checked on a regular basis.
Consult your Owner's Manual for complete instructions on using and maintaining your AQUA-MARE Aerobic MSTS.
