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1

Design

Plumbing the Water Change System
Plumbing the Water Change System

There are a few different ways that fishkeepers with many tanks choose to setup their water change systems. The optimal design for any particular fish room depends on the incoming water source, space available, and volume of water that will need to be regularly changed.

If you are on a well, you probably don't have to worry about paying a water bill or treating your water for chlorine or chloramine. Many people who have well water choose to run a continuous drip system, where new water is constantly being added. Since I have city supplied water that needs to be dechlorinated, I have to treat all water going into my tanks. So a continuous drip was not an option in my case.

Another common design is to use a large reservoir to store treated water. I didn't want to go that route because my space is somewhat limited. I needed a system that could give me filtered, tempered water on demand. And I wanted to be able to control flow to each tank using manual valves, and have drilled overflows to prevent flooding in case I forget I'm filling a tank (this happens a lot).

Fill System

Water coming into my fish room first runs through a dual-stage whole house filter system. The temperature of the water going to the tanks is controlled by a Delta shower valve , and the flow is controlled by a Pentair gate valve. The first section of the system is plumbed with PEX, because it was easy to tap into my existing plumbing.

I added a threaded 25 psi pressure regulator made for sprinkler systems to reduce the pressure in the line going to the tanks. This prevents pressure from building up at the individual tank valves and allows me to use irrigation compression tubing in some sections.

25 psi pressure regulator
25 psi pressure regulator

Each tank has its own fill line controlled by a Pentair gate valve with hose threading on the output side. I can screw on any hose attachment, including a Python hose adapter. My smaller tanks have a drip irrigation faucet fitting with irrigation tubing so I can do gradual water changes.

Fill Line Above 29 Gallon
Fill Line Above 29 Gallon

My larger tanks are fed directly from the faucets, with flow controlled using a combination of the valve at the tank and the system's main gate valve.

Hose Valve Above 90 Gal
Hose Valve Above 90 Gal

I can run slow, simultaneous water changes on several tanks at once with this system, or I can change out a lot of water on one tank very quickly. But the best feature is that I never have to fill and carry a bucket of water across the room! To quote the great rainbowfish keeper Gary Lange: "Gary don't carry", and neither do I.

Drain System

When it comes to draining water out of aquariums, there are obviously a few ways to go about it. You can use the old hose and bucket method. Or you can make the upgrade to a Python Clean and Fill System (which I use to perform water changes on my client's tanks). Or you can plumb the tank with a drain, either permanently by drilling a hole for a bulkhead, or temporarily using PVC. I prefer to drill aquariums whenever possible. A drilled overflow will never lose siphon the way an over-the-top PVC built one could. I wrote this post and this other post about drilling tanks if you are planning to try it.

3/4" Overflow Drain
3/4" Overflow Drain

Each drilled tank feeds a flexible braided hose that connects to a 1.5" PVC drain line which runs around the perimeter of the room. Below, you can see the PVC drain manifold underneath my 29 gallon rack.

1.5" Drain Manifold
1.5" Drain Manifold

There are a total of 4 sanitary tees spaced out along the drain line, and each can be expanded to handle multiple drains. The pipe starts about 12" off the floor, and runs about 20 feet around the room with a gradual decline to the floor drain.

1.5" Drain Line
1.5" Drain Line

You can see the 90 gallon sump overflow hose alongside the main drain pipe in these two photos .

Floor Drain
Floor Drain

This system took a couple months of planning and tinkering to implement, and I learned a lot about plumbing a fish room in the process. During that time I was constantly looking at examples of other people's systems to help influence my own. Hopefully seeing my design is helpful to someone else in the process of setting up a water change system.


6

Completed Filtration Install
Completed Filtration Install

**Important note: I am not a licensed plumber and this plumbing configuration may not meet building codes in your area. Please check your local regulations before taking on a project like this**

Why Add a Whole House Water Filter

The city water in my area is somewhat hard and sometimes has a chemical odor out of the tap, so I installed a whole house filter system to bring down sediment levels. This means we no longer need to keep a brita filter in the fridge for our drinking water, and I know the water going into all of my aquariums has had the heavy sediment removed.

This system is installed in front of my house's water heater. Removing sediment before water reaches the hot water tank reduces buildup inside, which can extend the life of the appliance.

The installation was pretty simple and I'll go over everything I used for the project here.

Supplies

This system uses two Pentek big blue 20" filter housings with a dual stage 50 / 5 micron sediment filter cartridge in front of a radial flow carbon cartridge. All of the filter parts used are listed below:

Sharkbite fittings and PEX tubing made the plumbing really simple. The process was the same as my fish room sink plumbing project (I listed the tools out in that post). The only difference is here I am working with the water supply line before my water heater, so it is 3/4" pipe rather than 1/2".

Mounting the Filter Housings

The first step was to secure a piece of plywood to the wall to support the weight of the lag screws that hold up the filter brackets. I used wood screws to attach the wood to the studs behind the drywall. Then I used 1/4" x 1" stainless lag screws and washers to attach the filter brackets to the wood. I tied the two housing tops together with a section of PEX before mounting them so that they would be level with each other on the wall.

Filter housings mounted to wall
Filter housings mounted to wall

With the housings mounted, all I had to do was plumb the system into the cold water line coming into the fish room.

Plumbing

Its important to "dry fit" all of your connections before making the pinch clamp connections, in case you need to make changes. Once a piece of PEX is clamped onto a fitting, its difficult (though not impossible) to remove. A 10 foot stick of PEX tubing is cheaper than a brass fitting, so cutting a new piece while testing out your configuration isn't a big deal.

Making a pinch clamp connection
Making a pinch clamp connection

My system has a bypass line with a ball valve above the filter housings so that I can shut off the flow to the filters. Without a bypass, changing the filters would require shutting off the water to the entire house. There is also a ball valve on either side of the filters so that they can be entirely isolated. Water will still flow to all of the downstream fixtures while I change the cartridges.

Sketch out your fish room plumbing before you start
Sketch out your plumbing before you start

I recommend drawing out your plan on paper before you start making connections. This should include the direction of flow through the system. The handle of a ball valve in the open position should point in the direction of water flow. The picture above shows all 3 valves open, but the bypass valve at the top remains closed while the filters are in use.

After I finished the bypass plumbing, I extended the PEX lines up to the ceiling to join with my cold water supply. I made the connection to the copper pipe using a 3/4" sharkbite fitting on both ends of the system.

3/4" Sharkbite Connection
3/4" Sharkbite Connection

This project took me a few days because I took my time figuring out where I wanted to tap into my existing pipes, but the actual plumbing could be completed in an afternoon if you have it planned out. Based on my usage the filter cartridges should last somewhere between 3-6 months. So I should only have to touch the system a few times a year.

Finished Plumbing
Finished Plumbing

2

DIY Sump for 90 Gallon Aquarium
DIY Sump for 90 Gallon Aquarium

I built a DIY sump filter for my 90 gallon freshwater aquarium using a standard Aqueon 20 long tank. There are a lot of great advantages to using a sump filter, especially on larger systems. A sump can hold several times more filter media than a hang on back or canister filter. Sumps also allow you to remove equipment, like heaters, from the display tank so that it is out of sight. Finally, since a sump can technically be any container that holds water, there is a lot of room for customization.

Overflow Plumbing

Gluing the Overflow Plumbing
Gluing the Overflow Plumbing

This system is using an Eshopps Eclipse (Medium) overflow, which requires drilling a hole for a 1.5" bulkhead. The overflow has two 1 inch bulkheads, which allows for a Herbie style overflow setup. With this configuration, the primary overflow valve is set partially closed, so that the water level in the overflow box rises to the top of the red secondary, or emergency, standpipe.

Herbie Drain
Herbie Drain

The partially closed ball valve limits the flow through the strainer, maintaining a siphon that runs quietly. A small amount of water flows down the open emergency standpipe. This configuration is popular in reef tanks for its quiet operation and ability to handle a lot of flow without worrying about a clogged strainer causing the display tank to overfill.

Sump Design

This sump is built from a standard size Aqueon 20-long, with three glass baffles siliconed in place to create the different sections. The first two baffles force water flowing into the sump down through the mechanical media and then up into the second section. The third baffle sets the minimum water level in the sump at about 6", or half the height of the tank. This leaves room for roughly 9 gallons of water to overflow from the display tank into the sump in the event of a power failure or pump failure.

Empty 20 Gallon Sump
Empty 20 Gallon Sump

Egg crate style lighting diffuser creates dividers that hold the media in place and keep it off the heaters. I cut sections of the lighting diffuser down using wire snips, and attached the pieces to each other with zip ties. The first section has a platform that holds the media up above the bottom of the first baffle.

Lighting Diffuser Platform
Lighting Diffuser Platform

The second section of the sump holds the bio media and heaters. Here I made a platform for the media to sit on, as well as a divider for the heaters. I also made an air driven circulation device using an old sponge filter housing without the sponges. The two intake tubes sit on the glass bottom of the sump below the diffuser, pulling water from the bottom up to the top of the media. The idea was to create more movement across the media and oxygenate the water before it gets returned to the aquarium.

Circulation Lift Tube Installed
Circulation Lift Tube Installed

Filtration Media

This sump is using a combination of polyester quilt batting, thick sponges, bio rings, and lava rock for filtration. Water flows from the overflow pipes into a basket that holds a layer of polyester batting, which catches most debris and fine particles before they get into the rest of the sump. I covered how cheap and awesome quilt batting is as a filter media in my post about DIY filter hacks.

Polyester Batting
Polyester Batting

The bottom of the filter basket is lined with a 1 inch think coarse sponge. This traps debris the batting didn't catch and allows the water to drain evenly through the sides and bottom into the 3 inch layer of sponges below.

Mechanical Filtration Basket
Mechanical Filtration Basket

In the second chamber is 7 pounds of lava rock, with 4 one-pound bags of bio rings on top. Lava rock is highly porous and often used in pond filters because it is cheap to buy in bulk. I picked up a 7 lb bag for less than $10 at a home improvement store. I got the bags of bio rings, as well as the coarse sponge for the filter basket, from aquariumcoop.com.

Biological Filtration
Biological Filtration

The heaters are positioned in front of the bio media so they are easily visible and accessible if I need to make an adjustment. The final chamber houses the pump, which sends the water back up to the display. This section has extra space I can use to add activated carbon, purigen, or any extra media I may want to cycle.

DIY Sump in Service
DIY Sump in Service

The entire build for this DIY sump cost me under $100, not including the submersible pump ($20) and overflow ($110). Compare that to canister filters like the Fluval FX4 that, while effective, run well over $250 and provide virtually none of the advantages of a DIY sump.