Meridian App Connection Guide
ReefBreeders / App Guide
Connecting your Meridian to the app
Meridians shipped from around June 2026 onward connect over Bluetooth or wifi. Earlier lights connect over wifi. This guide covers account setup, tank setup and both connection methods, start to finish.
Before you start
Phone permissions
- Location: required. Both iOS and Android tie wifi scanning and Bluetooth scanning to location permission. This is a platform rule, not our choice, and pairing cannot work without it.
- Bluetooth and wifi: both need to be switched on, whichever connection method you use.
- Notifications: strongly recommended, and required for some features including acclimation mode.
Your network, if you are using wifi
- 2.4GHz only. The light cannot see or join a 5GHz network. If your router broadcasts both bands under one name, you may need to separate them temporarily.
- Have your wifi password on hand. It is case and symbol sensitive.
- Firewalls: if your network runs one, make sure port 8883 is open.
Bluetooth or wifi
Both give you full control of the light. What differs is what happens beyond your phone.
Simplest to set up
Bluetooth
A direct connection between your phone and your light. No router, no password, no network settings. Your indicator LED will be blinking purple when the light is in Bluetooth mode and ready.
Available on Meridians shipped from around June 2026 onward. Older lights need a firmware update to use it, so contact us if you would like yours updated.
Needed for groups
Wifi
Connects your light through your router to a central server, which is what makes groups possible and lets several lights share one program. Your indicator LED will be blinking blue when the light is in wifi pairing mode.
Works on every app-capable Meridian, old or new.
Create your account
Download the ReefBreeders app, then set up an account before adding any hardware.
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Sign up with your email
The app emails you a six digit verification code. If it does not arrive within a minute, check your spam folder.
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Set a password
It must contain either a special character or a capital letter.
Set up your tank
Tanks are how the app organises your lights. It is worth thinking about the structure before you add anything.
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Name it and describe it
Give the tank a name, choose saltwater or freshwater, and enter the water volume.
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Share your location
Recommended. Your tank's location drives the moonrise, moonset and moon phase simulation, as well as the natural sunrise and sunset modes.
Premium users can optionally set an offset location instead, to simulate sunrise and sunset times from a reef or anywhere else in the world.
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Add a profile picture
Optional. A photo of the aquarium makes tanks easier to tell apart at a glance.
Add your device
Check your indicator LED before you reach the connection choice, because the light has to already be in the mode you are about to pick.
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Tap Add New Device
On your tank page. If this is your first light, it is the large button in the middle of the screen.
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Open Meridian and choose Meridian
Tapping Meridian expands it to show two options. Choose the plain Meridian entry. Meridian Dual Panel is for a feature that has not been released and does not apply to current lights.
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Choose Wi-Fi or Bluetooth
A Choose Device Connect panel slides up from the bottom. Neither option is selected by default, so tap one to check it, then tap Continue.
Match this to what your light is actually doing. Blinking purple means the light is in Bluetooth mode. Blinking blue means it is in wifi pairing mode.
Wrong mode? Use the reset key included with your Meridian to press and hold the reset button for about 5 seconds, until the indicator LED changes color. Release, and the light reboots into the other mode. This resets the device and deletes internally saved programming.
Connect over Bluetooth
Far simpler than wifi. There is no network to join and no password to enter.
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Check the light is in Bluetooth mode
The indicator LED should be blinking purple. If it is blinking blue, the light is in wifi mode. See section 05 for how to toggle.
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Pick your light from the list
The app scans and lists nearby Bluetooth-enabled Meridians, each shown as Meridian followed by its device ID, for example Meridian-6A9BD8. Tap the one you want.
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Confirm you got the right one
If several lights are plugged in at once, the one that goes solid purple after connecting is the one you are now connected to.
Connect over wifi
More steps than Bluetooth, because your light has to be handed your network credentials. iPhone and Android diverge in the middle, so find your platform below before you tap anything.
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Check the light is in wifi pairing mode
When first plugged in, the app board boots through red, green and blue, then settles on blinking blue about once per second. That is where the connection process begins.
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Tap Ready
The same screen on both platforms. What happens after it is where they differ.
On Android, the first time through, the app asks you to enable wifi permissions before it can continue.
iPhone: join the light's network yourself
On iPhone there is an extra step in the middle. You have to put your phone onto the network the light is broadcasting before the app can hand over your home network details.
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When you see Check Connection, stop
Do not tap it yet. Go to your phone's wifi settings and connect to your light's own network.
You will probably see a warning about an unsecured network, which just means it has no password, and another about no internet connection. Both are normal. Your light is not providing internet.
Do not join the light's network before the app tells you to. If you connect early, your phone loses its internet connection and setup fails. -
Return to the app and tap Check Connection
Once your phone is on the light's network, the indicator LED goes solid blue.
Android: the app handles it
Android skips that entirely. There is no Check Connection button and no trip to your settings. After Ready, the app goes straight to picking your home network, much like the Bluetooth flow.
Both platforms: hand over your network
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Choose your home network
The app shows a list of networks for the light to join. Pick your 2.4GHz network and enter the password. It is case and symbol sensitive, so tap the crossed-out eye icon to reveal what you typed and check it before confirming.
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Confirm and connect
The app asks you to confirm you want to connect. The indicator LED blinks blue or green rapidly, then settles on solid green, which means the light is connected to your router.
From there the app moves on to naming your light.
If it does not settle on solid green and the app moves on to naming your device, name and save it anyway, then perform a reset and let the light reinitialise its wifi connection. If that fails twice, the wifi password is the most likely culprit, so re-check it character by character.
Name and test your light
The last two steps are the same whether you connected over Bluetooth or wifi.
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Name the light
The screen shows the device ID at the top, which is fixed, and a name field below it that you can edit later. A name describing where the light sits over the tank is far more useful than an ID. Front Left Meridian 24, for example.
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Test it
The next screen lets you move the color sliders. The light should respond, though there may be a couple of seconds of delay. If it reacts, you are connected.
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Continue to scheduling
Tap continue to add a schedule, or skip for now to go to the main menu.
The reset button
The reset button behaves differently depending on how old your light is. Check which set of rules applies to you before holding anything down.
June 2026 onward
Lights with Bluetooth
Hold about 5 seconds, until the indicator LED changes color. Purple means the light is rebooting into Bluetooth mode, blue means wifi mode. Watch the color rather than counting, and release once it changes.
This one hold does both jobs. It switches connection mode and restores factory defaults, so the light has to be added to the app again afterwards.
There is no separate longer reset on these boards. The 5 second hold is the only one you need.
Earlier lights
Wifi only
Hold 4 to 5 seconds: the light forgets its wifi credentials but keeps its schedule. It goes from solid green to blinking blue, ready to pair again.
Hold 10 seconds until it flashes yellow, then release: a full reset.
Release as soon as you see yellow. Holding past that gives solid red.
Indicator LED colors
The indicator LED on the light's endcap is the single most useful diagnostic you have. This is the full list.
Bluetooth mode
| Indicator | What it means |
|---|---|
| Blinking purple | In Bluetooth mode and not currently connected to your phone. This is the normal resting state, and the light's program keeps running. |
| Solid purple | Connected to your phone right now. Useful for confirming which light you are editing when several are nearby. |
Wifi mode
| Indicator | What it means |
|---|---|
| Red, green, blue repeating | Powering up and running through its boot cycle. |
| Blinking blue, slow | Not connected to wifi. The light is broadcasting its own network and is ready to pair. |
| Solid blue | Connected directly to a phone or tablet. Normal during pairing. |
| Flashing green, fast | Connecting to your router. |
| Flashing blue, fast | Trying to reach your router and hitting a problem. Usually a wrong password, or a router pushing it onto 5GHz. |
| Solid green | Connected to your router. This is what you want. |
Everything else
| Indicator | What it means |
|---|---|
| Yellow-green | Factory test mode, from eight button presses. Not a connected state. Press once more to exit. |
| Solid yellow | Appears during a full reset. Release the button as soon as you see it. |
| Any color plus a yellow blink every second | The temperature sensor is not properly connected. Contact support. |
| Solid red | A problem with the app board, or the reset button held too long. Unplug for 30 seconds and try again. |
Groups
Groups let several identical lights share one program, edited in one place.
- Wifi lights only. Groups run through the central server your lights connect to via your router. A Bluetooth connection is a direct one-to-one link between your phone and one light, so there is nothing in the middle to coordinate a group.
- Devices must match. Same type and same spectrum. A Meridian cannot be grouped with an Edge bar or a Photon.
Troubleshooting
The questions that come up most often.
How does the new reset button sequence work?
On lights with Bluetooth, use the included key to press and hold the reset button for about 5 seconds, until the indicator LED changes color. Purple means it is rebooting into Bluetooth mode, blue means wifi mode. Watch for the color change rather than counting seconds. Doing this restores factory defaults, so the light will need to be added to the app again.
Does the purple indicator LED stay solid?
No. It blinks whenever your phone is not actively connected, which is most of the time, and that is entirely normal. The light's program keeps running regardless. It goes solid only while your phone is connected to it.
Does my light need to stay connected to run its program?
No. The program is saved on the light itself. A constant connection is not required, and your schedule will keep running through a wifi outage or with your phone nowhere nearby.
What color should my indicator LED be?
On wifi, solid green. Occasional drops to blinking blue are normal, since routers drop connections and the light usually recovers on its own. On Bluetooth, blinking purple is the correct resting state whenever you are not actively editing the program.
Why can't I add my Bluetooth light to a group?
Bluetooth is a direct connection from your phone to one light. Wifi connects lights to a central server, which is what makes it possible to program several as one. To sync Bluetooth lights, apply the same schedule to each one individually. The effect is the same.
The app found my light's wifi network but will not connect.
Forget the light's network in your phone's wifi settings, close the app completely, perform a reset on the light, then start the process again from the beginning.
My light shows a yellow-green LED and will not respond.
That is factory test mode, reached by pressing the button eight times. It is not the solid green that means connected. Press the button once more to exit, let the light boot, then check the LED again.
My light dropped off and is blinking blue.
Unplug it at the wall outlet for 30 seconds and plug it back in. That resolves most dropped connections without a reset. If it is still blinking blue afterwards, tap the three dots next to the light's name in the app and choose Reconnect.
Can I switch a light from one tank to another?
Not directly. You would need to reset the light, delete it from the app and add it again under the other tank. Worth planning your tank structure before you set lights up.