Add Automatic Water Changer (AWC)

As a hobbyist, your top priority is maintaining the quality of your water. This requires regular or as-needed water changes, which can be a tedious task. However, with the HYDROS Control, you can automate this process and eliminate the need for manual water changes. The Automatic Water Changer allows you to set specific parameters for when and how much water should be changed, ensuring optimal performance and safety without the hassle of hauling and spilling water.

How Does the AWC Work?

To understand how the AWC works, we first need to understand the states of the AWC system.  

• IDLE State: The AWC/ATO is not engaged in this state. The AWC is NOT scheduled to activate, and the top sensor on the sump is “Wet,” Therefore, the ATO Pump is not pushing freshwater into the sump to replenish evaporated water.
• ATO State: In this state, the High-Level Water Sensor is reporting “dry,” the ATO part of the AWC is active, and the small ATO pump will push freshwater into the sump to replenish normal evaporation. In this state, the AWC is NOT active or running.   
  
  TIP: The Automatic Water Changer IS also your ATO. When the AWC is not active, then it becomes your ATO. For example, when you configure the output below, it will ask you for three different pump locations:

  • ATO Output Device: A pump within your freshwater reservoir pushes freshwater into your sump to replenish evaporation.
  • Drain Output Device: A pump in your sump drains saltwater from your tank.
  • Fill Output Device: A pump located by your saltwater reservoir pushes new saltwater into your sump.
• Drain State: The ATO part of the AWC has been disabled in this state. The ATO pump will ignore the high-water sensor and not push freshwater into the sump. The Control WILL turn the Drain Pump ON until the bottom sensor reports “Dry” or until the timer (defined by the user) is expired, whichever comes first.
• Fill State: The ATO part of the AWC is still disabled in this state. The ATO pump will ignore the high-water sensor and NOT push freshwater into the sump. The Control will turn OFF the Drain Pump and turn ON the Fill Pump until the top-water sensor reports “Wet” or until the timer (defined by the user in Advanced Settings) is expired, whichever comes first. At this point, HYDROS will allow the water level to settle for 10 minutes before returning to IDLE State.

During a typical day, your AWC acts as a regular ATO and employs the High-Level Water Sensor to identify water evaporation. It then activates the ATO pump to transfer water from the freshwater reservoir to the sump. The AWC typically alternates between the IDLE and ATO states during normal operation.

When a schedule for an automatic water change is set and initiated, the AWC will shift to the DRAIN mode. Afterward, it will deactivate the ATO and activate the Drain Pump until the bottom-water sensor indicates “Dry” or the timer, which was set by the user, runs out. Following that, the AWC will transition to the FILL mode and activate the Fill Pump to transfer new saltwater from your reservoir to your sump until the top-water sensor detects “Wet.” Lastly, once the process is complete, the AWC will return to the IDLE state and activate ATO as necessary.

Frequently Asked Questions for AWC:

Can I still use my regular HYDROS ATO with the AWC?

Yes! You will need to remove the ATO Output from the HYDROS app. When configuring the AWC, you will be asked for the location of your ATO water sensor AND your ATO pump!

Can I use another non-HYDROS ATO unit with the AWC?

Yes! You must turn OFF your regular ATO when the AWC is active. You want your ATO to avoid adding fresh water simultaneously; your AWC is draining or adding new saltwater into your sump.

Do I have to schedule an automatic water change to use the AWC, or can I use it as a one-time water change to activate it manually?

You must schedule the AWC to work correctly. At this time, manual “triggering” is not supported. If you want to trigger a one-time AWC, you need to create a schedule and set it to trigger immediately 5-10 min from now.    

What happens if I lose power in the middle of an AWC?

In case the power outage occurred during the AWC’s draining process and it is currently in the DRAIN state, once the Control powers back on, the AWC will automatically switch to the FILL state. This means that even if the AWC had drained for a while before the power outage, it will fill your sump with saltwater instead of freshwater from the ATO.

If the power goes out while the AWC is filling, the ACW will remember it was in the middle of the filling process when the power comes back on and will continue to fill. This prevents the ATO from filling the low-water sump with freshwater instead of saltwater.

In case of a power outage while the AWC is inactive, the Control will remember and switch back to IDLE or ATO mode if the sump water level is low due to evaporation.

What happens if the AWC Output gets interrupted due to a “Depends ON?”

If the AWC is interrupted by a dependency such as the return pump turning OFF (NOT a power loss), the Controller will turn the entire output OFF. This means it will turn OFF both AWC and ATO.  

When the dependency clears, the AWC will still remember its last state! So the AWC will pause until the dependency is removed, and at that point, the AWC will wait 5 minutes (the user can change this time delay) and then:

• If a Low-Level Water Sensor is defined: The HYDROS will resume in the state it left off. For example, if the AWC were in a DRAIN state, it would continue to drain until the Low-Level Water Sensor reports dry or the Advanced Settings Max Drain Time expires, whichever comes first. If the AWC were in a FILL state, it would continue to add new saltwater until the High-Level Water Sensor reports as WET or the Advanced Settings Max Fill Time expires, whichever comes first.
• Suppose a Low-Level Water Sensor IS NOT defined (draining solely based on time). In that case, the HYDROS will resume in FILL state and add new saltwater to the sump until the High-Level Water Sensor reports as wet or the Advanced Features Max Fill Time is exceeded, whichever comes first.  

Here is what you’ll need to get started:

• One Water Sensor was installed and configured. You can add a second sensor, but it is not required.  
  
  TIP: If you still need to configure your water sensor input, please follow the instructions here ^[1].
• ATO pump physically installed to either a Drive Port or a WiFi Outlet
• A pump to drain water out from your sump
• A pump to fill your sump with new saltwater. (To prevent a siphon, we recommend you use a peristaltic dosing pump for this application)

Step 1: Create the AWC Output

1. From the STATUS screen on your HYDROS app, top on the three horizontal dots to the right of the OUTPUTS label and select “Add New Output.”
2. Tap on the + symbol at the bottom right of the page
3. Type in the name of your new output and then tap “Create”

Step 2: Configure your AWC

• Type: Select Automatic Water Change (AWC)
• High-Level Input: This is the high-level water sensor. When the AWC is in IDLE or ATO state, it will serve as your ATO water sensor and trigger the ATO pump to add fresh water to the sump when dry. When the AWC is in the FILL state, it will trigger the Fill pump to stop when wet.
  
  TIP: To see a list of all inputs available on MULTIPLE devices, you must first create a Collective ^[2]. Otherwise, only inputs on the same device will show.
• Low-Level Input: This is the low-level water sensor. When the AWC is in the IDLE or ATO state, it will ignore it. When the AWC is in a DRAIN state, the Drain Pump will stop when the sensor reports dry.
  
  TIP: To see a list of all inputs available on MULTIPLE devices, you must first create a Collective ^[2]. Otherwise, only inputs on the same device will show.
• Drain Duration: This field only shows if the user does not specify a Low-Level Input. This allows the user to set a predetermined time for the drain pump to turn ON.  
  
  TIP: The user can STILL add a drain time limit as a safety feature. You can add that below in the “Advanced Settings”
• ATO Output Device: This is the location of your ATO pump. If you connected the pump to a drive port or WiFi outlet, here is where you specify the location.  
• ATO Power Safe Range: It allows you to specify a power use range considered “acceptable.”  If power consumption is outside the range, a notification will trigger if selected.
  
  WARNING: This option is NOT available if the “ATO Output Device” is assigned a WiFi strip outlet.
• ATO Power Notification Level: It allows you to select the notification level that triggers if the power consumption falls outside the “Power Safe Range.”
  
  WARNING: This option is NOT available if the “ATO Output Device” is assigned a WiFi strip outlet.
• Drain Output Device: This is where you connect your Drain Pump.  
• Drain Power Safe Range: It allows you to specify a power use range considered “acceptable.”  If power consumption is outside the range, a notification will trigger if selected.
  
  WARNING: This option is NOT available if the “Drain Output Device” is assigned a WiFi strip outlet.
• Drain Power Notification Level: It allows you to select the notification level that triggers if the power consumption falls outside the “Power Safe Range.”
  
  WARNING: This option is NOT available if the “Drain Output Device” is assigned a WiFi strip outlet.
• Fill Output Device: This is where you connect your Fill pump.  
  
  TIP: We highly recommend using a peristaltic pump instead of a regular DC/AC pump to prevent siphoning and backflow issues.  
• Fill Power Safe Range: It allows you to specify a power use range considered “acceptable.”  If power consumption is outside the range, a notification will trigger if selected.
  
  WARNING: This option is NOT available if the “Fill Output Device” is assigned a WiFi strip outlet.
• Fill Power Notification Level: It allows you to select the notification level that triggers if the power consumption falls outside the “Power Safe Range.”
  
  WARNING: This option is NOT available if the “Fill Output Device” is assigned a WiFi strip outlet.
• Active Modes: This allows you to select which modes this output will be active and which modes should turn OFF.
  
  TIP: The AWC should be active in Normal mode for most folks. The Controller will take care of following the schedule you create. If you create an AWC schedule that is only active during Water Change, then when the Controller is in Normal mode, it will not run the AWC.
• Depends On: This feature allows you to turn the ENTIRE output based on the status of another output. To enable, select from the list of available outputs.  
  
  WARNING: If the AWC Output turns OFF based on dependency, it will TURN OFF the ENTIRE output. This means that the AWC and ATO will both be disabled. To disable the AWC but leave the ATO part unaffected, use the Depends On on the AWC Schedule Settings.
  • Dependency Mode: This allows you to turn the output ON or OFF based on the other output.
    • OFF if OFF: Will turn the current output OFF if the output it depends on is OFF.
    • OFF if ON: Will turn the current output OFF when the output it depends on is ON.
    • ON if OFF: Will turn the current output ON when the output it depends on is OFF.
    • ON if ON: Will turn the current output ON when the output it depends on is ON.
• Is Invisible: If you choose to hide the input from the status screen, it will only become visible on pages that have “Show Invisible” selected.
• Enable ATO Advanced Settings: If you are an expert, this feature will allow you to tweak the ATO part of the AWC settings to suit your system better.  
  
  TIP: You will get notifications once the ATO pump advanced settings have been exceeded. If you set the Notification Level to NONE, the AWC output will not send you any notifications that pertain to the ATO pump ONLY.
   
  • Minimum OFF Time: This allows you to specify what is the minimum time the ATO pump should be OFF
  • Maximum OFF Time: This allows you to specify what is the maximum time the ATO pump should be OFF
  • Minimum ON Time: This allows you to specify what is the minimum time the ATO pump should be ON
  • Maximum ON Time: This allows you to specify what is the maximum time the ATO pump should be ON
  • Run Past Max ON time: This allows you to specify if you want the ATO pump to remain ON even if the “Max ON Time” has been exceeded.
  • Notification Level: This allows you to specify the level of notification you want when any of the advanced settings have been exceeded
• Enable Drain Advanced Settings: If you are an expert, this feature will allow you to tweak the Drain pump part of the AWC settings to suit your system better.  
  • Drain Maximum On Time: This allows you to set the MAXIMUM time the Control can turn the Drain pump ON if the Low-Level Water Sensor remains dry or unchanged. If the Low-Level Water Sensor shows DRY before the time expires, the Controller will stop the drain pump. Likewise, if the Low-Level Water Sensor does not change to dry before the time expires, the Controller will stop the drain pump when the time expires.  
  • Drain Run Past Max On Time: This allows you to set the drain pump to continue running even if the Drain Maximum On Time has been exceeded.  
    
    TIP: Even if you select to run past max on time, you will still receive a notification level if you select the notification option below.
  • Drain Notification Level: This allows you to select the level of notification you want to receive if any Drain pump advanced settings are exceeded.
• Enable Fill Advanced Settings: If you are an expert, this feature will allow you to tweak the Fill pump part of the AWC settings to suit your system better.  
  • Fill Maximum On Time: This allows you to set the MAXIMUM time the Control can turn the Fill pump ON if the High-Level Water Sensor remains DRY or unchanged. For example, the Controller will stop the Fill pump if the High-Level Water Sensor shows WET before the time expires. Likewise, if the High-Level Water Sensor does not change to WET before the time expires, the Controller will stop the Fill pump when the time expires.  
  • Fill Run Past Max On Time: This allows you to set the Fill pump to continue running even if the Fill Maximum On Time has been exceeded.  
    
    TIP: Even if you select to run past max on time, you will still receive a notification level if you select the notification option below.
  • Fill Notification Level: This allows you to select the level of notification you want to receive if any of the Fill pump advanced settings are exceeded.

Step 3: Save

• Upload your changes to the cloud. 

Step 4: Create AWC Schedule

To activate the AWC Output and the automation, you MUST create an AWC Schedule. To learn how to create the schedule, please click here ^[3].