DIY Fish Room Auto Water Change System
Over the last few years I’ve accumulated. . . a number of aquariums. I’ve got a 220 gallon display tank. Seven 40 breeders,Two 55s, Six 10s,and a 33 long. So I find myself doing a lot of water changes. And I have a job, and a family, So a couple of months ago I decided it was finally time to invest in a system to automate those water changes. Today I’m going to show you how I built it, all of the equipment I used, and how it works. Links to all of the supplies can be found down in the video description,And at the end I’ll go into a few of the reasons that I did it this way so if you have questions please be sure to watch the whole video.
The first and most important requirement for a project like this is a water source. If you don’t have direct access to your pipes, then a utility sink is a good substitute. In my case, I recently added a sink to my fishroom using pex tubing which I knew I could tee off as the source of my water. But please, if you plan to make changes to your home’s water supply, just make sure you know what you’re doing or consult a licensed plumber. The second most important requirement for this project is a way to drain the excess water from your tanks. The most common way is to drill the tanks or use overflow boxes and connect them to a central drain system. I recently completed a big drain overhaul project and all of my tanks now empty to a 2 inch PVC pipe that runs to a floor drain. I will link to a video I did about that if you need more information.
The first major piece of equipment in this system is a rough-in shower valve. This allows me to set one stable temperature for all of the water that runs through the system. There are many variations of this valve by Delta and other manufacturers but I went with this model because it has connections for pex tubing. These valves take a cartridge which does the actual balancing of the pressure and temperature. You can buy the cartridge separately but I just bought a trim kit which was less expensive. I won’t get into a whole lot of detail on these valves in this video but just know that if you take a shower and you set the temperature and it stays there the whole time, it’s one of these vales that’s doing the work. The second major piece in this system is a series of water filters. The main purpose of these filters is to remove chlorine but they prevent any nasty stuff in my water supply from reaching the aquariums. They use the very common 10 inch by 2 and a half inch cartridges found in both the hobby and home water filters. The connections are all 3/4″ inch threaded and the housings are easy to remove, allowing me to replace the filters as needed. They also come with mounting brackets.
The first stage will be a polypropylene sediment filter to catch most of the larger nasty stuff. The second stage will be a 5 micron Matrik x CTO Carbon block filter, aka “the workhorse”,which will remove the majority of the chlorine. The third stage will be a 5 micron CTO+ carbon block filter, also known as the “Chlorine guzzler”. This removes any residual chlorine that makes it past the first carbon block filter. Now it’s really important to note that there are no chloramines in my municipal water supply. If you have chloramines then you’ll need to pick different filters so that’s something to keep in mind as you plan a system like this. The system will be controlled by a programmable irrigation timer that’s sold at most hardware stores. I went with a Rainbird unit that has the ability to turn water on and off to six different zones. I only plan to use four zones for now but this gives me the ability to expand the system in the future. You may only need one zone or way more than four depending on how many tanks you have. The timer connects to solenoid valves and these are really the key to the entire system. The timer is programmed to send power to the valve, causing a plunger to rise, which unseals the valve and allows water to flow through.
Since I have multiple valves, they will be plumbed together into a manifold. This manifold will consist of four identical sets of components, one for each zone. It starts with a 3/4″ PVC tee which will be connected via a 3/4″ nipple to the solenoid valve. Then the solenoid will connect to a 3/4″ check valve. These check valves are very important because they prevent backward pressure on the solenoids. I couldn’t find threaded check valves so these will be glued into adapters on each side. After the check valves comes a pressure regulator. This reduces the water pressure on each zone down to 25 psi which is important. Without these regulators there would be way too much pressure on the lines running to the tanks and they could blow out. The last piece in each zone is a 3/4″ PVC union. This just makes it easier to remove each section to deal with any issues. To get the water from the manifold to the tanks I will be using pvc pipe with small screw-in water valves. They’re sold by Jehmco and have a flow rate of 10 gallons per hour which will be plenty for the amount of water I’m planning to change. Other miscellaneous supplies for the project include: 3/4″ pvc pipe, pvc cement, Teflon tape, pvc cutters, a drill, drill bits, screws, brackets, pliers, and probably a few other things that will come up along the way.
The first stage of the assembly is to construct the manifold. This can be done a number of ways but I think it’s easiest to put together each zone and then connect the zones to each other at the end. Step one is to put Teflon tape on both sides of the nipple that will be screwed into the PVC tee. When in doubt, use more Teflon tape than you think is necessary to minimize leaks. Screw the nipple into the tee and tighten with pliers. Next, screw the solenoid valve onto the other end of the nipple. Be sure to pay attention to the direction that the water will flow. It’s marked on the valve. Then apply Teflon tape to one of the slip by threaded adapters and screw it into the other end of the valve. Now it’s time to assemble the second part of the zone. Grab two more slip by threaded adapters, the pressure regulator, and the threaded union. Apply Teflon tape to all of the threads and screw one of the adapters into the top of the union. Then screw the top of the pressure regulator into the bottom of the union and reassemble it. Then screw the last adapter into the bottom of the pressure regulator. The rest of the zone will need to be glued together. Grab some PVC cement, a couple of small lengths of 3/4 PVC pipe, and the check valve. I use gloves when doing this because I always end up with glue on my hands.
The first step is to glue one of the PVC pieces into the adapter on the top portion. Then glue the bottom of that piece to the top of the check valve. Be sure to hold your arm directly in front of the camera. Next, complete a similar process for the bottom of the zone. Glue a piece of PVC to the adapter on the top of the solenoid valve. Then finally glue the other end into the bottom of the check valve. Here is what one of the manifold zones looks like fully assembled. And here is the fully completed manifold with all four zones connected together.
Now that the manifold is complete, it’s time to start installing all of the components in the fishroom. I decided to hang the manifold first and build outward. You may choose to do it differently based on your setup. First I grabbed a piece of plywood that was left over from another project and hung it on the wall. Then, I used 3/4″ brackets to attach the manifold to the plywood. Next I connected my filters to the manifold with 3/4″ nipples and screwed the brackets into a 2×4. The 2×4 is just screwed into the studs from the sides. Using another piece of plywood wouldn’t have allowed the filters to sit in line with the manifold. Next came the plumbing. I cut my cold water line and tee’d it over to the shower valve, which I mounted to a piece of wood between the studs. Yes, my cold and hot water lines are on the wrong sides. They cross as they connect to the sink but I didn’t want them to be on the wrong sides of the valve.
Next, I tee’d off the hot water line and ran it over as well. I decided to use the bottom part of the valve that usually runs to a tub as a kind of second sink faucet. I plan to leave a hose connected here to use any time I need to fill a tank in a hurry. Next I ran the shower portion of the valve over to a shutoff and then to the water filters. When I want to set the temperature of the water, I can use the shower handle that came with the trim kit. But I don’t plan to leave it attached so that I don’t accidentally bump it. The next step was to mount the irrigation timer. Again I just used a piece of plywood. I won’t go into the details of the wiring because it’s easy and the unit comes with instructions. You just need a length of sprinkler wire and some wire nuts. It’s really not any more complicated than wiring a home stereo. The final pieces to assemble are the runs of PVC with the water valves in them.
First, mark the locations of your valves so you know where to drill the holes. Next, use a drill bit that’s sized appropriately for your tap and drill on your marks. In my case it’s a 5/32″ bit but your tap should come with instructions. Be sure not to drill through the back side of the pipe and remove any excess PVC shavings. This is what the tap looks like. It’s very similar to a drill bit and can be ordered along with the valves. Just drill into your existing hole for a few revolutions. You don’t need to go too far. This is what it looks like once you’ve completed your threads. Then take one of your valves and wrap the threaded side in Teflon tape. And finally, screw the valve into the pipe. It should be water tight. Mounting the pipes above my tank was easy in some spots and more difficult in others. It really just depends on the room.
For this zone I just connected to the zone on the manifold and ran the pipe above the tanks with an elbow fittings. For other zones I had to get more creative to work around my air system and the existing plumbing in my basement. But once all of the pipe in hung, just connect some quarter inch tubing to the nozzles and run them to your tanks. I used irrigation tubing but airline tubing will work as well. Just be sure to have it connect securely to your tank as far away from your overflow as possible. This minimizes the amount of new water going down the drain.Programming the timer is very simple. In my case, Zone 1 will run upstairs to the 220. Zone 2 will be my 10 gallon tanks. Zone 3 will be my 40 breeders. And Zone 4 will be my 55 gallons and the 33 long. I will have the water changes happen overnight, And stagger them so that I’m never at risk of running out of hot water. As you can see, the flow is excellent and requires zero manual intervention.
Now for the discussion about some of the decisions that went into this system. The first question may be why to do a system like this instead of just a continuous drip system. Well I’ve been running a drip system on all of my tanks for a couple of years, and while it does help a lot, it doesn’t change nearly enough water and is difficult to . Also, I have fairly hard water so my drip emitters were always clogging up because they’re partially closed and full of water. Another question may be about why I don’t just use a huge container to store water and treat it before pumping it into my tanks. Well, I don’t really have the space for that,and I don’t even buffer my water for a number of reasons, and I definitely don’t want to maintain a dosing pump. So pushing the water through the filters is a much better option for me. Lastly, I just want to acknowledge that this system was inspired by several systems built by other great people, especially Ted Judy, Aquarium Co-Op, Beantown Aquatics, and others. Hopefully it inspires you to try something similar. And if you do, please show it off and leave a link down in the comments. Thanks so much for watching and until next time, have a good one.