An Over-Engineered 1-Liter Brine Shrimp Hatchery that Does It All!

[Astyanax]

Hi guys:

Been lurking a long, long time, I figured it's time for me to give something back! While this is not exactly specific to reef-keeping, I feel there's still an application, and I hope fishkeepers of all kinds might find this interesting.

For almost a year, I've been hatching brine shrimp every other day for baby swordtails using the soda bottle method. While I've been mostly successful, I've found a number of small "pain points" that I would like to solve by building a more robust housing for the same method:

1. The soda bottles need to be replaced every 6-8 uses. Making fresh caps and removing labels becomes tedious.
2. Darkening the entire area and aiming a light at just the right spot to entice the hatched brine shrimp to go to the bottom is difficult.
3. New LED lamps don't provide heat.
4. Temperature inconsistencies results in 18-36 hour hatch times.
5. Unplugging the air pump to extract shrimp can be tricky when it's the same tube for both air and water.
6. Using the soda bottle bottom as a splash guard often results in this "lid" falling in.
7. The whole process of extracting shrimp and setting up for a new batch takes more time than it should.

I fancy myself a little bit of a "maker" and tinkerer (I like to make cool things), so I thought this might be a fun opportunity to over-engineer a solution that solves all these problems. I hope it would also be fun to put together, and an opportunity to learn a few new skills. So I made a list of requirements:

1. The chamber must be a 1L bottle for 800mL of water, easily replaceable.
2. No more DIY bottle caps. No more label removal!
3. A 25w heater to keep the temperature in the high 80s, consistently bringing hatch time to less than 24 hours.
4. Air pump contained in the housing.
5. A permanent light for the top that is not a desk lamp.
6. An LED light for the bottom to draw the hatched shrimp down.
7. The entire chamber encased, so it can be kept dark when needed.
8. A splash cover that won't fall in.
9. Airstone instead of bare air tube, reducing noise.
10. Individual switches for each electrical component (there are 4!).
11. Dedicated spigot to decant hatched shrimp.
12. The entire rig self-contained and portable.
13. Removable panels to access any component as needed.

After some sketches and planning, I had a rough idea of how this is all going to look and work:



I'm not great with woodworking, but I do have a bandsaw, so I think I can cut all the pieces I need from hobby board from the hardware store.

Massive, massive overkill? You bet! But I'm hoping this new setup will reduce turnaround time and solve all those pain points. I'm already very deep into this project, so I will start posting progress and photos over the next few hours.

If you have any other thoughts, ideas or concerns, please chime in!

Thanks for reading,

Bill

[Astyanax]

After taking lots of measurements and making some more sketches, I modeled the entire housing in Google SketchUp:



The back wall will be covered, but the front and side will have removable panels (using magnets?) that will allow me to get to all the areas.

[Astyanax]

Here is the basic structure of the entire hatchery. The vertical walls are 3/4" poplar hobby board, sold at 3-1/2" wide at Home Depot. I only needed to cut them to length. The base is a 5-1/2" wide piece of the same stuff, and the top is a 5-1/2" wide piece of 1/4" board. Again, only cut to length!

The hole is 1-9/16" in diameter, only because that was the only forstner drill bit I had that was close to 1-1/2" in size!



To finish the support elements, I added two 1/2" square dowels to the front. All attachments were made with wood glue and 1-1/4" finish nails.



The rest of the wood elements will be framing for the access panels, as well as the panels themselves.

[Astyanax]

For the bottle that will serve as my hatching chamber, I chose the 1L bottle of Fiji water:



There are several benefits to this choice:

1. It's readily available.
2. It has a standard size mouth.
3. The label doesn't need to be removed to see the contents unobstructed; because there is no labeling on the sides, I need only rotate it 90 degrees.
4. It doesn't have to be washed; I can use the water that's already inside!

Before, I was making pump-friendly bottle caps by drilling a hole and gluing an airline connector in the cap. But on Amazon I found "cola bottle adapters," at less than $13 shipped for a pack of 20.



These will last me forever, and I won't need to worry about glues or other toxins getting into the water. I was getting a massive shrimp die-off after 6-8 uses; I suspect the epoxy I was using might have been leaching toxins into the water as it aged.

[Astyanax]

Next, I added some cross bars to begin building up the framing that will support the panels. The longer side strips are are 1/2" strips cut by bandsaw from 1/4" thick hobby board, and the short front blocks are 1/2" square dowels, all available at Home Depot.



I made sure I positioned the height of the bars just right so that they would help support the bottle, but still be as high as possible, just a tiny bit higher that the cut-off bottom (top?) of the bottle.

I also cut a piece of scrap clear acrylic to size with my bandsaw, and test-fit it on top of these bars. This will serve as my splash guard, and framing and panels will hold it in place.



I realized at this point that getting the bottle in and out will be tricky unless I cut a slot for the nozzle of the cap! I cut this out with a hacksaw.

[Astyanax]

Not too exciting, but next I filled my nail holes with Bondo:



After sanding those down, I put in all my vertical framing, which consisted of 3/4" strips of 1/4" board and 1/4" square dowels to finish it out. These were all secured with wood glue and clamps.

The back/side panel was cut from some crap MDF that I had, and was gllued in with wood glue and nailed in with tiny 1/2" finish nails.



Almost done with the main body; it's about to get more interesting and fun!

[reelredfish]

Wow nice job following along

[Vinny Kreyling]

subscribed!

[Astyanax]

The front and side panels need to be removable. I had this idea of embedding some rare-earth magnets in the panels and frame, and then filling over them with Bondo so they'll be invisible. I found these magnets at Home Depot:



So I drilled 3/8" holes in the frame and panel boards, about 1/8" deep. A forstner drill bit enabled me to provide a flat surface for the magnets. I then superglued them in.

After this, I filled the holes with Bondo, and sanded them down flush. Once painted, they should disappear!




For a knob, I picked up these half-inch "button plugs" from Home Depot:



I attached them to the panels with #4 screws.



All three panels ready to go!



The magnets and knobs worked perfectly! The panels don't align with the frame of the box 100% perfectly, you can't tell unless you look really closely.



Next, I'll drill some holes for power cords and air tubing, then it's ready to paint!

Now we're all caught up to real-time. Thanks for reading!

Bill

[reelredfish]

Keep on with the updates we are enjoying it.

[Hans2278]

Brilliant work, following


Sent from my iPhone using Tapatalk

[twitchy]

Wow, great work and planning! Thanks for sharing

[Astyanax]

Originally Posted by reelredfish

Wow nice job following along

Originally Posted by Vinny Kreyling

subscribed!

Originally Posted by reelredfish

Keep on with the updates we are enjoying it.

Originally Posted by Hans2278

Brilliant work, following

Originally Posted by twitchy

Wow, great work and planning! Thanks for sharing

Thank you so much for the kind words guys, I really appreciate it! I'm glad you're enjoying the build!

Today I'll be painting and planning out the electrical stuff.

Bill

[Astyanax]

Since the panels were ready, I went ahead and painted them.

Something I had to keep in mind was the fact that paint settles on different materials in different ways. It wants to soak into wood, but not filler or glue, which means it looks matte on wood and shiny on other materials. Since I was working with all those materials (plus MDF), I needed something that was more than a paint, but also a coating. So here's my Dream Team when it comes to finishing this kind of stuff:

1. The Rustoleum 2X flat black served as a primer, so everything else would stick a little more evenly. It also gave the wood a little something to soak up first.
   
2. I followed with the Plastidip, which gives everything a slightly rubberized coating along with a slightly "rough" texture. This has the effect of evening out the coating across all materials, filling some of the gaps, hiding some of my poor sanding technique, and providing a small bit of protection.
   
3. Next, I sprayed again with a couple coats of the Rustoleum 2X flat black, to once again even out the color, and to protect the rubber a little.
   
4. I finished out with Testors Dullcote, which is a clearcoat that protects the finish. In my experience, it is hands-down THE BEST matte clear-coat you can use on anything.

The result of all of this is a very hard "plastic" kind of finish that wipes clean with water.



Once the panels were done, I drilled holes in the housing for power cords, switches and airline.





Time to paint the housing itself!

Bill

[reelredfish]

Another good update.

[Astyanax]

Okay, the painting. So most of the day was spent in painting the main housing, using the same spray cans mentioned above. I won't take you through every grueling step, but suffice it to say my garage still smells of fumes!

Once it was done it looked pretty nice!



Now I get to work on the insides! To start, I wanted to deal with main power first. I picked up a black power cord and a 4-outlet power strip from Home Depot, both very cheap. The power cord came pre-stripped, but I had to cut the plug off and strip the wires from the power strip myself.



Next, I ran the black power cord through the hole in the back of the housing, and then soldered the wires to the power strip, matching the wire colors. I used heat shrink tubing to insulate the wires.

I have very little experience soldering, so I spent some time studying techniques on YouTube first!



After running a larger piece of heat shrink tubing over the work (I had slid it on the cord earlier!), my power cord was done and ready to drive power into the housing.



I mounted the power strip on the back-side wall of the housing using some heavy-duty double-sided mounting tape. Then I used zip tie mounts and zip ties to secure the cord to the inside walls.



I finished by applying hot glue to the hole where the power cord comes out, securing it in place and taking tension off the cord on the inside.



Done with power! Tomorrow I'll start working on hooking up the upper light.

Thanks for reading!

Bill

[Nrdau]

Wow great job. Better over engineered then under

[twitchy]

Looking good, what are the overall dimensions of the cabinet? Your attention to detail and organization is inspirational... Curious to see what your sump looks like haha

[Astyanax]

Originally Posted by twitchy

Looking good, what are the overall dimensions of the cabinet? Your attention to detail and organization is inspirational... Curious to see what your sump looks like haha

Heh, no sump; I'm in the freshwater world at the moment, taking a break from saltwater. Neon swordtails breeding like rabbits on baby brine shrimp! If you live in the San Diego area and want freshwater fish, come take some away!

The dimensions are 11-3/4" long, 5-1/2" wide, and 16-3/4" high.

Bill

[Astyanax]

The first internal component I tackled was the overhead light. I picked up one of these LED pucks from Amazon for ten bucks:



(In retrospect, I wish I had chosen the cool white instead of warm white, but this will serve just fine.)

Because I have to run cords through holes, every component in this build will have to have its cord chopped up, shortened, and wired to a switch. So I took the puck out of its outer housing, and chopped up its cord in preparation for splicing.



For switches, I had a bunch of these red/green/black push-buttons, so I decided to use them. I would have preferred rocker switches that I could "flip" on and off, but I didn't want to have to cut rectangular holes.



After soldering and heat-shrink-wrapping the one side of the power cord, I prepped it for attaching to the switch.



This is particularly tricky, because the cord has to be wired to the switch from the other side of the hole!



But once it was done and the button fully affixed to the side, I slathered a bunch of hot glue over all the exposed metal parts, insulating and securing it all.



Then I attached the cord to the zip-tie mounts with the power cord and turned it on. Igor, it's alive!



One component down, three more to go. Later today I'll set up the heater.

Thanks for reading,

Bill

[Astyanax]

I have four components (upper light, lower attracting light, heater, pump) for this build, but only three holes for switches. I had planned not to need one for the heater, but as I gave it more thought, I realized that I need to be able to easily turn off the heater as well.

So I put another switch hole next to the others. That one went very poorly, probably due to the fact that my thick paint finish would rather be broken off than cut through. But the hole is intact!



For heater selection, I went with the smallest submersible heater I could find, but still adjustable. I need to get the hatchery's temperature up to the mid-80s Fahrenheit, and all the tiny heaters are pre-set to 78 degrees. No good! So I settled for this 25-watt Penn-Plax model from Amazon:



I recognize that this is serious overkill for one liter of water, but I didn't really have any choice if I wanted to keep the temperature consistently high.

Similar to what I did with the light, I chopped up its cord and started splicing. This will use a red-colored push-button (I only have the three colors).



I wired it up similarly to the overhead light, and then tested it in some water.



Setting it to 82 degrees Fahrenheit gave me a water temp of 85 degrees, and it seemed to stay there. Perfect! I do expect it to run a little hot, because water temperature will continue to rise a couple degrees in that small of a volume while the heater cools down. At least it won't drop below 82 degrees, so I'm satisfied. I'm hoping for less than 24 hours hatch time with that temperature.

Next up, hopefully later today, the tiny LED light to attract the hatched shrimp back down to the bottom!

Thanks for reading,

Bill

[Astyanax]

One of the most frustrating parts of working with a brine shrimp hatchery is separating the shrimp from the hatched and unhatched egg shells. Originally, I struggled with putting a tiny flashlight near the bottom while the whole thing was covered with a towel. It worked, but only if the flashlight didn't fall over. I plan to solve that by adding a small LED light near the bottom of the chamber, that way I can turn it on or off as needed.

Some weeks ago, I picked up this kit of assorted electronics from Amazon to help with various makery projects. It got my attention not only because it had a wide assortment of parts, but also came with a downloadable PDF that contained lessons and guides for making lots of small electronic projects from these parts. I'm not very good with electronics, so this was right up my alley!



This kit had exactly what I needed to assemble a very simple white LED circuit, and it had instructions for how to do it.

To power the whole thing, I dug up an old unused power adapter, which generates 5 volts at 1 amp of current. The instructions said that's what I would need, and it was easy to find.

After following the picture and adding the right type of resistor (220 ohms), I had a working LED light!



I was ready to wire it up directly, again using solder and heat shrink tubing.



This little bulb is very bright, and it definitely projects more light from its end than from the sides. So I decided to recess it a little. This will ensure that the light output is directed at the bottle, and doesn't flood the whole chamber with light.

Once I had it in position, I secured it with hot glue. Messy, but effective! But I forgot the power transformer plug might get in the way. So I simply bent the wires down a little, and the plug fit just fine.



I wired up the switch, same as the others, and re-secured some of the cords to the side wall. Works great!



Three switches down, one to go!

[Astyanax]

The final interior component is the air pump and tubing assembly. I've had good luck with these Top Fin pumps from PetSmart, so I picked one up from my local store:



As usual, I cut the cord and started splicing. I'll be using a black push-button switch for this component.



But before I could install it in the housing, I had to deal with something I've encountered before in air-powered projects: vibration! We all know, air pumps want to "walk" around on whatever hard surface they're located, until they're loudly buzzing against the side of their enclosure!

I always keep a supply of "anti-vibration" or "anti-skid" padding, as I use it in all kinds of projects. It's not only great for suppressing vibrations, but it's like the bottom of a mousepad: it grips any flat surface very nicely, so I've glued some on all kinds of tools and things in my garage.



In this case, I needed a piece about 5-3/4" x 3-1/2" for the floor of the box.



Then I glued it into the box using 5-minute 2-part epoxy. It's not going anywhere. Instant padded rubber floor!



But that's not enough to hold a pump in place. It won't make much noise anymore, but it'll still walk a little. So I cut a "strap" of the same material (It's very stretchy), and screwed one end to the floor of the box. Once the pump is settled in, I'll screw in the other side. This not only secures the pump in one place, but enables me to remove/replace it as needed.



After that, I finished my wiring work, attaching the wires of the pump to the switch and power cord and insulating with hot glue.



All four buttons complete!



I attached a long piece of airline tubing to the pump, and secured the strap around the pump with a second screw.



One more round of re-securing the cords with zip ties, and all wiring is done!

[Astyanax]

To finish the air connections, I attached a check valve and fed the air tubing through its hole into the bubble chamber area. The check valve also serves as a tension relief on the tubing, as it can't fit through the hole.



To make sure I can get bubbles all the way to the bottom of the water bottle, I needed a piece of rigid tubing. Unfortunately, here in North San Diego County, all the local fish stores have been driven out of business thanks to the fact that there are two PetCo and PetSmart stores per square mile around here. And they don't carry something like rigid airline tubing.

So I raided the junk drawer and took one of the many crazy straws my kids were collecting:



Perfect diameter!



I hooked this up to the flexible air tubing, and then test fit with the Fiji bottle. Looks like a good fit!



Okay, the air pump is done, all components are done! But I still have a few finishing touches and some minor plumbing adjustments to make before I can fire it up.

Thanks for reading!

Bill

[Astyanax]

Next, I needed to work on the tubing and fittings for the bottom of the bottle, where I get the shrimp out and remove the bottle for cleaning.

I used two of these metal ball valves for airline tubing:



I had drilled the hole in the back side of the box a tiny bit too small, so when I pushed the valve into it, the fit was so tight that no glue was necessary. Instant shrimp spigot!



Inside the box, I needed to run a tube from the bottom of the bottle to the spigot, but also make it relatively easy to detach. Those metal barbed fittings do not release airline easily, but I had a soft plastic connector to make it easy:



For plumbing, that's pretty much it!

Next, I had to address the acrylic splash guard.