Hydros Reviews

[mjw]

I'm considering switching from Apex to Hydros. I'd love to hear from both sides what you love or hate about your Hydros or Apex controller for your reef tank? Thanks!

 

[Bear22]

I'm considering switching from Apex to Hydros. I'd love to hear from both sides what you love or hate about your Hydros or Apex controller for your reef tank? Thanks!

Reef Dudes on YT just did a long podcast comparing the two systems. You might find some useful information there that might answer some of your questions.

 

[Jamie9]

I'm a big fan so far (started my first tank on Hydros November 2025 and it is running strong). I started with a "START" and a wifi power strip. Then I added an XP8 and an X4 later on. No complaints, and it has allowed me to do everything I've attempted to do with it so far. If I were to do it again, I'd sit down and figure out what are all the "nice to have" things that I might want to do a year from now...and then buy Hydros controllers to cover that...instead of adding on as I wanted to expand. I'm sure I would have wound up with a different combo. A lot of people have complained about connectivity issues with the Wifi power strip, but mine has never been a problem. That said, I'd just get the XP8 instead. Having the ability to monitor the current on your return pump is really a nice feature. I actually had originally gone Hydros because the Maven looked like it might actually be coming...I've since decided we will probably never see that...but I'm very happy with what I wound up with anyway. (And not sure I'd even buy the Maven if it came out now anyway...I'm really not testing everything ever day).

 

[dank.reefer]

I like my Hydros system. I have 3 tanks running on it. It is reliable and stable. If you set one up I would strongly encourage setting up a dedicated WiFi access point that is for just the Hydros. I know a lot of people get upset when the WiFi connection poops out and this $20 fix cures that. It is actually what Hydros recommends in their set up instructions. That being said unless you are using WiFi power strips the WiFi connection isn't hyper critical. WiFi is just an interface for you where as the system controllers themselves are on a closed loop CAN bus.

Hydros also just recently released an API version of their app so if you you are handy with programming it is an open interface that can be integrated with other devices and also home automation systems. For instance if you have a smart thermostat in your home and your tank is running hot, with the proper programming in the Hydros API you can have the Hydros turn on the AC.

I know another user who has accent lights in his living room connected to a WiFi strip. When different alerts pop up in the Hydros system different lights turn on. That way even if he is away from his phone or tank he will know that there is something that needs attention.

So far I control all of my, skimmers, ATO's Heaters, UV sterilizers, dosing pumps, and return pumps with Hydros and haven't had any issues for 3 years.

 

[mjw]

I like my Hydros system. I have 3 tanks running on it. It is reliable and stable. If you set one up I would strongly encourage setting up a dedicated WiFi access point that is for just the Hydros. I know a lot of people get upset when the WiFi connection poops out and this $20 fix cures that. It is actually what Hydros recommends in their set up instructions. That being said unless you are using WiFi power strips the WiFi connection isn't hyper critical. WiFi is just an interface for you where as the system controllers themselves are on a closed loop CAN bus.

Hydros also just recently released an API version of their app so if you you are handy with programming it is an open interface that can be integrated with other devices and also home automation systems. For instance if you have a smart thermostat in your home and your tank is running hot, with the proper programming in the Hydros API you can have the Hydros turn on the AC.

I know another user who has accent lights in his living room connected to a WiFi strip. When different alerts pop up in the Hydros system different lights turn on. That way even if he is away from his phone or tank he will know that there is something that needs attention.

So far I control all of my, skimmers, ATO's Heaters, UV sterilizers, dosing pumps, and return pumps with Hydros and haven't had any issues for 3 years.

Thank you! Great comments and suggestions for the wifi fix :)

 

[mjw]

I'm a big fan so far (started my first tank on Hydros November 2025 and it is running strong). I started with a "START" and a wifi power strip. Then I added an XP8 and an X4 later on. No complaints, and it has allowed me to do everything I've attempted to do with it so far. If I were to do it again, I'd sit down and figure out what are all the "nice to have" things that I might want to do a year from now...and then buy Hydros controllers to cover that...instead of adding on as I wanted to expand. I'm sure I would have wound up with a different combo. A lot of people have complained about connectivity issues with the Wifi power strip, but mine has never been a problem. That said, I'd just get the XP8 instead. Having the ability to monitor the current on your return pump is really a nice feature. I actually had originally gone Hydros because the Maven looked like it might actually be coming...I've since decided we will probably never see that...but I'm very happy with what I wound up with anyway. (And not sure I'd even buy the Maven if it came out now anyway...I'm really not testing everything ever day).

Yeah I'm not holding my breath on Maven but would be excited if it worked as advertised...

 

[mjw]

I'm a big fan so far (started my first tank on Hydros November 2025 and it is running strong). I started with a "START" and a wifi power strip. Then I added an XP8 and an X4 later on. No complaints, and it has allowed me to do everything I've attempted to do with it so far. If I were to do it again, I'd sit down and figure out what are all the "nice to have" things that I might want to do a year from now...and then buy Hydros controllers to cover that...instead of adding on as I wanted to expand. I'm sure I would have wound up with a different combo. A lot of people have complained about connectivity issues with the Wifi power strip, but mine has never been a problem. That said, I'd just get the XP8 instead. Having the ability to monitor the current on your return pump is really a nice feature. I actually had originally gone Hydros because the Maven looked like it might actually be coming...I've since decided we will probably never see that...but I'm very happy with what I wound up with anyway. (And not sure I'd even buy the Maven if it came out now anyway...I'm really not testing everything ever day).

I love that xp8... it make a huge difference!

 

[n2585722]

I have a large collective of Hydros on mine. I have a build thread here on R2R you can get to by clicking on the "My Tank Thread" banner in one of my post. Then go to page 6 post # 119 to get to the Hydros info. There are post throughout the rest of the build thread about the Hydros system. I would add a post every time something new was added to the system. The start was back when they first came out with the X4 controller. I had a specific use for it at the time and was using a Digital Aquatics Archon at the time I got the first one. The first one went in the garage at my mixing station. I did connect it to the Archon using inputs and outputs to send signals back an forth since I did not have any Hydros controllers at the tank and the Hydros was used to control the ATO and AWC for the tank. I now have only Hydros controlling things at the tank and at the mixing station. I have quite a bit automated, I also use an iV and a X10 to do alkalinity testing 4 times a day and use the results to adjust the KH buffer added 4 times a day. Other things like calcium, phosphate, nitrate and magnesium I test once a week but I do have static inputs setup in the Hydros that I add the results to so the test info is in the Hydros so I can graph it when I want to do that. Hopefully the post in the build thread will give you some insight into how to get the Hydros systems to do what you want it to do. Things have changed quit a bit since I first started using Hydro but I did try and add post about the changes and how I used them in my system. Just like the way I used to control my RODI to refill the DI reservoir or the mix tank. It used to require several outputs but now they have a RODI output type that will take a low level input and also a full level input so it is turn on the output when the low level input goes low and turn off the output when the full level goes wet. In the build thread there are some post about how I did it before that output was brought out I still use something similar for the mix ready signal where I press a push button after adding the salt mix to the mix tank and it is ready to use. There is an output that is latched on and it stays on until the System transfers the contents of the mix tank to the fresh salt water reservoir once it goes low. Once the transfer is completed the Hydros turns on the RODI unit and refills the mix tank with DI water. All I have to do is add the salt mix and press the mix ready pushbutton to let the system know it is ready to use.

 

[BryanM]

I went from Apex to Hydros and am quite happy. Support from Coralvue is far better.

 

[Kokanuty]

I really like my Hydros system. Have not used Apex but so far so good. I do wish they would hurry with some kind of display we can set up. Preferably on iPad a nice customizable look with graphs etc.

I did plan ahead and have one remaining piece to get and that is the Hydros Blenny. I was originally going to start with the X10 but doing some cost calculations I determined what I got with the Blenny will be more ports and less expensive.

I was able to remove all power bricks which is great, expensive, but nice.

 

[afboundguy]

I never had Apex but I have enjoyed my Hydros system so far. I like the alkalinity testing with the iV and X10 and even of the Maven does come out I'd be in no rush to buy it.

I really like the fact that each module (minus wave engines and wave engine lites) can act as a "brain." I like that redundancy. If my main one loses connection or craps out I have several other ones that can take over.

I also like how robust the system is. Even though I haven't had an Apex I have seen plenty and they just don't seem as robust.

I agree about making sure it's on a dedicated 2.4 ghz. I have had much better connection ever since I did that especially with the wifi power strips.

 

[Court_Appointed_Hypeman]

I am a big fan of my hydros, running nonstop since 2022. Xp8 sense and drive right now, waiting on the maven. Would have gone with their dose system, but I built my own before they announced it.

I wish I could code on it, but you can do some pretty absurd logic with virtual devices, and they have added a lot too since I last touched my programing. I run my plank autofeeder on it, one of their auto feeders. I bought extra ato pump and water level meters, but all of the original parts are still running. The little pump has been doing kalkwasser for 4 years nearly now in the ago and still going strong. Everything on my tank runs on it. I did cheat and buy some tuya power strips that hydros recognizes.

But its great, ive had individual modules lose connection to the network or hang a couple times a few years ago, the rest of the collective picks it up 0 issues. Until I could be at home to reboot if I needed.

 

[fryman]

I have both. Apex is better on the coding/software front. Hydros is good and maybe easier to get used to but it's programming and trending capabilities have a long way to go to match the Apex.

The multiple brain thing From Hydros appears to be a marketing gimmick to me. The one thing that never fails is my controller. What fails all the time? Probes, "energy bars", and wifi. It's like carrying a spare bike frame on a long road trip. If my bike frame breaks things really went off the rails and I likely have bigger problems. What I really need is spare tires, brake pads, and bike chains.

Both systems get the main things right. Temp, orp, & pH monitoring, and outlet controls work well. Hydros depends more on wifi and Neptune makes it easier to hard-wire everything. I trust copper hard-wired connections much, much (much) more. But Hydros has the option to go hard-wired so maybe I'm being unfair.

Slight tangent but pet peeve of mine: salinity monitoring is a crapshoot on both. I've had it working for months without issue, then suddenly salinity goes on the fritz. 99% of the time salinity alarms are probe/controller error. So right now I just don't trust continuous salinity measurements on any system. I don't know why this is so hard to get right but it seems to be universal because multiple companies fail to handle this measurement realiably, at least for me.

 

[n2585722]

I have both. Apex is better on the coding/software front. Hydros is good and maybe easier to get used to but it's programming and trending capabilities have a long way to go to match the Apex.

The multiple brain thing From Hydros appears to be a marketing gimmick to me. The one thing that never fails is my controller. What fails all the time? Probes, "energy bars", and wifi. It's like carrying a spare bike frame on a long road trip. If my bike frame breaks things really went off the rails and I likely have bigger problems. What I really need is spare tires, brake pads, and bike chains.

Both systems get the main things right. Temp, orp, & pH monitoring, and outlet controls work well. Hydros depends more on wifi and Neptune makes it easier to hard-wire everything. I trust copper hard-wired connections much, much (much) more. But Hydros has the option to go hard-wired so maybe I'm being unfair.

Slight tangent but pet peeve of mine: salinity monitoring is a crapshoot on both. I've had it working for months without issue, then suddenly salinity goes on the fritz. 99% of the time salinity alarms are probe/controller error. So right now I just don't trust continuous salinity measurements on any system. I don't know why this is so hard to get right but it seems to be universal because multiple companies fail to handle this measurement realiably, at least for me.

The salinity measurement's on all controllers use conductivity probes. Anything that gets between the probe points will affect the readings. Also bacteria can grow on the probe points and change the conductivity also. Also any voltages in the water will also skew the readings they can be due to inductive transference and not a connection exposed to the water. I use two probes and when the difference between them get high I will clean and recalibrate both probes. One is in my iV and the other is in the sump in the refugium section. The iV is set to take a salinity measurement every 2 hours. I don't miss coding but my previous controller a Digital Aquatics did not have that either. I have a quite complex system and there is nothing I have wanted my Hydros to do that i have not found a way to do it with the Hydros yet. I was even controlling my RODI and refilling my DI reservoir and transferring water from the mix tank to the fresh salt water reservoir when it went low if the the mix tank contents was ready for use. It would then refill the mix tank with RODI from the RODI unit. This was before they came out with the RODI output type. I did switch over to that output once it came out though. Also if you are using the XP8, Launch or Start for your AC control then wifi loss will not affect the controllers in a collective but they will not be happy without wifi though but they will continue to work. I rarely have a wifi issue it is normally a issue with the internet connection. I was without internet for a week once and the controllers continued to work like they were setup to do. I had to use a blue tooth connection on my phone to connect to them. They have added the emergency mode since then so I can connect using that on my iPad without internet access. I do have my on wifi router and do not use one from my service provider. The ones from the service provider may also loose wifi if the internet link with the service provider goes down. So without internet my wifi still functions and the wifi power strips still work since the communications is local during normal operations without internet. Of coarse you cannot change any settings without internet but you can still change an output from off, auto or on if you need to do that for some reason. Communications between the the controllers in a collective is through the command bus cables so wifi is not required for the controllers in a collective to communicate with each other to keep things going. Basically instead of having a main brain and modules with Hydros each module has a brain and can work independently or together with other modules to form a control system. There is one that acts as a main brain but another can take over that role if it is needed. On a system with a main brain and the rest are modules if you loose the main brain then it will no longer work at all until the main brain is fixed or replaced. With a system where each module has a brain they can still try and control things without one of the modules. You would still loose any inputs or outputs on that lost module. At least the others would continue to run as good as they can without the lost module.

 

[n2585722]

I have both. Apex is better on the coding/software front. Hydros is good and maybe easier to get used to but it's programming and trending capabilities have a long way to go to match the Apex.

The multiple brain thing From Hydros appears to be a marketing gimmick to me. The one thing that never fails is my controller. What fails all the time? Probes, "energy bars", and wifi. It's like carrying a spare bike frame on a long road trip. If my bike frame breaks things really went off the rails and I likely have bigger problems. What I really need is spare tires, brake pads, and bike chains.

Both systems get the main things right. Temp, orp, & pH monitoring, and outlet controls work well. Hydros depends more on wifi and Neptune makes it easier to hard-wire everything. I trust copper hard-wired connections much, much (much) more. But Hydros has the option to go hard-wired so maybe I'm being unfair.

Slight tangent but pet peeve of mine: salinity monitoring is a crapshoot on both. I've had it working for months without issue, then suddenly salinity goes on the fritz. 99% of the time salinity alarms are probe/controller error. So right now I just don't trust continuous salinity measurements on any system. I don't know why this is so hard to get right but it seems to be universal because multiple companies fail to handle this measurement realiably, at least for me.

Here is a graph of both my salinity probe in the sump and a sampled input of the one in the iV. The one in the sump varies more than the sampled one does but it is only sampled every 2 hours. The reading on the right is the last readings for each probe. I think I did calibrate a couple of times during the graph period but it was only the 35ppt point and I did that in the tank after checking the tank water with a refractometer to make sure it was still 35ppt.

 

[Court_Appointed_Hypeman]

I have both. Apex is better on the coding/software front. Hydros is good and maybe easier to get used to but it's programming and trending capabilities have a long way to go to match the Apex.

The multiple brain thing From Hydros appears to be a marketing gimmick to me. The one thing that never fails is my controller. What fails all the time? Probes, "energy bars", and wifi. It's like carrying a spare bike frame on a long road trip. If my bike frame breaks things really went off the rails and I likely have bigger problems. What I really need is spare tires, brake pads, and bike chains.

Both systems get the main things right. Temp, orp, & pH monitoring, and outlet controls work well. Hydros depends more on wifi and Neptune makes it easier to hard-wire everything. I trust copper hard-wired connections much, much (much) more. But Hydros has the option to go hard-wired so maybe I'm being unfair.

Slight tangent but pet peeve of mine: salinity monitoring is a crapshoot on both. I've had it working for months without issue, then suddenly salinity goes on the fritz. 99% of the time salinity alarms are probe/controller error. So right now I just don't trust continuous salinity measurements on any system. I don't know why this is so hard to get right but it seems to be universal because multiple companies fail to handle this measurement realiably, at least for me.

Have you tried using virtual devices yet? I cant think of anything I cant do with them. I didnt realize it at first so I thought it was limited too

 

[n2585722]

Have you tried using virtual devices yet? I cant think of anything I cant do with them. I didnt realize it at first so I thought it was limited too

I assume you are referring to outputs that do not have an assigned output device and are used by other outputs for control. I do that quite a bit. One of the first things I controlled by my Hydros system was my RODI unit. The did not have the RODI output type at the time so I used several outputs to do that instead. I have screenshots that I will post here for my DI refill which uses 2 inputs and 4 outputs to do that. Only one of the outputs controls an actual output device and that was a solenoid that controls RODI output going to the DI reservoir. The first 2 screenshots below are the inputs showing their settings. The first one is for the low level sensor the other is the full level sensor in the DI reservoir tank. I was using combiner outputs so to use these inputs I had to create a couple of outputs that used these inputs to control them. Those are screenshots 3 and 4 below. I created a latch output that would keep the solenoid output in until the full output goes wet otherwise it would turn off when the DI low output in the case would go to wet state of the input sensor so that would not work since I want the output to keep filling until it reaches the full sensor. The 5th screenshot below is the latch output. It has 2 inputs one is the DI low output that turns it on which will turn on the output that actually controls the solenoid. That output is the second input for the latch and keep the latch on until both of it's inputs are low since it uses the OR combiner mode. That keeps the output that powers the solenoid on after the DI low output goes low once the water level is at that sensor. The last output here which is the 6th screenshot below is the one that actually powers the solenoid. It has 2 inputs one is from the DI Fill latch output and the other from the DI full output. The one from the DI full output is inverted so that make it a high logic when the output is actually low so it is a high when the water level is not at the full sensor. This output uses the AND combiner logic so as long as the water level is below the full sensor and the DI fill latch is on it will stay on. If either inputs change state the output will turn off. Since I had to tanks I was filling with the RODI I also had a solenoid on the input to the RODI unit which had an output setup so if any of the three outputs controlling it as inputs were on it would turn on. One was the DI fill output that is shown here, one is the mix fill output and the last is a timer so the RODI will turn on for a few minutes every 2 hours to refill the bladder tank if needed. That is used by the ice maker in the fridge. The last screenshot below is a logic diagram of these outputs. I figured I would post this for anyone that would like an example of using outputs for logic to control other outputs. I have since started using the RODI output type which does simplify the setup for this quite a bit since it has two inputs the low level input and the full input. It also can control a booster pump and a flush valve also but those are optional and it will work without setting output devices for those.