Back into the hobby - 29G Biocube Plan and Build (Long and Drawn Out)

[Somnifac]

I kept tanks for many years, both reef and fresh (though mostly fresh (Rift Lake Cichlids)) but I've been tankless for quite a while. I thought that it was about time that changed.

So, this thread will serve as a very long and drawn out planning and build process. I'm in absolutely no hurry, and I want to take the time to do things right and neatly.

I found a used 29G Oceanic Biocube with stand, and plan on bringing it back to life. Overall my intent is to set it up as a coral only (with some inverts for cleaning) mixed reef, with mostly soft and LPS corals. I'll consider SPS only after it has been set up for quite a while.

Part I (What I Have)

As I mentioned above, I picked up a 29G Biocube (Oceanic) we a stand. The cover had been modified, had some holes drilled in the top, and had the lights and fans messed with. Step one was to cut the hood since I'll be going in a completely different direction than the previous owner. I'll clean up and repurpose the holes in the top for new switches, install new lights and fans to keep them cool. Step two was to clean out the dried up junk left in the tank. A soak with some white vinegar and a bit of scrubbing took care of the most unsightly bits.

Moving onto the stand. The stand is mostly in good condition, with the exception of the black vinyl covering on the top and base of the stand. I will be disassembling this and recovering them with some black upholstery vinyl with the help of some upholstery staples.

Part II (Build Plans)

As of now, my intent is to build my system around a DIY controller built upon a reef-pi (See the work that @Ranjib has put into the software over in his thread in the DIY forum). That will control all power routing, temperature monitoring, lighting levels, and (in the future) wavemaker controls.

The first phase of the build will be the hood. This tank will be in a bedroom, so I'd like to keep the cover on it to keep noise and evaporation as low as I can. With that in mind, I plan on installing an SB Reef Light 16" panel into the hood.

This brings me to question #1: Does anyone know the dimensions of the Nano Heatsink that RapidLED sells? If I could mount the panel to the heatsink with thermal adhesive, that should help me keep the temps down, w/ 92mm the fan mounted on the heatsink, plus 2 fans in the hood to direct airflow.

Since the SB Reef Light has UV LEDs, which I would expect to end up yellowing the plastic splash guard, I will be cutting out an area of the splash guard, framing (and securing) in a piece of glass.

Control will be accomplished by wiring the dimming circuit to the reef-pi system, through a 5V PWM to 10V analog circuit.

All fans will all be at the very least manually adjustable. I'd like to run a temperature probe to the hood to monitor temps and have them ramp up as needed. If anyone has any experience w/ controlling fans w/ a Raspberry Pi I'd love to hear. Since the Pi itself outputs 5V PWM, that would be awesome to use that. Since I haven't looked that far ahead, I just don't know if the 12v PWM controllable fans use 5V or 10V PWM.

I don't anticipate doing anything special for the return pump, just a properly sized pump to get proper flow through the rear chambers. In the rear chambers I plan on:

• Chamber 1: Skimmer. I'm looking at either the Hydor Slim Skim or the Tunze 9002. I'm all ears if anyone has feedback on either.
• Media Basket and Fuge. Fuge light on the back. Pretty normal stuff here.
• Heater wherever it will fit.

For flow, I was looking at a Jebao PP-4 or 2. I'm looking this way with the hope of eventually ditching the controller and controlling directly w/ the reef-pi.

Typical live rock and sand will go in once it's ready. Nothing earth-shattering there.

So, that's where I am now. Over the next couple of months, I'll add posts here recording what I've done, what's worked, what didn't, and how I screwed all sorts of things that should have worked up.

 

[nautical_nathaniel]

I'm in absolutely no hurry, and I want to take the time to do things right and neatly.

A great philosophy to have with the planning process

From what I can tell, it looks like you're headed in a great direction! Be sure to post some pics when you get a chance!

 

[Ranjib]

I'm stoked to see your BC29 build thread.
I just removed the hood for my biocube, and I am glad I did it. I don't think splashing will be a big concern. I use mp10 without any lid, have no issue. Unless you keep any fish which can jump (though I am keeping a 6 line wrasse for almost 2 years now), lid is not required. Evaporation will be a concern, and you may need an ATO. This will also solve heating related issues.
You don't need fuge you have skimmer and chemical filtration, I am able to grow most sps just with a skimmer and chemical+ mechanical filtration. But having fuge will help with nitrate reduction as well a pod population. Tunze skimmer is good, AquaMax HoB is the best, but expensive.
Godspeed

 

[Somnifac]

I finally had a chance to recover the top and bottom panels of my stand (original thin vinyl was in sorry condition). A Joann's Fabric just moved locations near me, so I got a grand opening 50% of deal on a couple of yards of black vinyl and I went at it with a staple gun.

Result? Well, I'm certainly not an upholster. That much was obvious. But, you have to open up the doors and look underneath the top panel, or flip the whole stand over to see the bottom to be able to see that. From all normal viewing angles it looks fine. Perfectly acceptable and passable, though I may have added 5 lbs to the stand in staples.

The parts for my reef-pi have also started to trickle in. Got some resistors. My relay board came in. More stuff should arrive tomorrow (gotta love Amazon Prime shipping to an Amazon Locker; yes, they deliver on Sunday). I'll be able to prototype stuff soon, but I'm still trying to figure out how I want to handle the enclosure.

Do I want to do it in multiple enclosures? One for the brain, one for the relay board and outlets? One big one? Something off the shelf? Something with 3D printed parts? I'm not sure. I'm going to have to think on it.

@Ranjib

While noise it's certainly a concern, the biggest concern is spillover from the light. I'd like to keep it as focused into the tank as I can. Fish aren't an issue, as there will be none in the tank. Temperature will be the big hurdle, but with the big heatsink and a fan directly mounted to that, and fans in the vents in the hood itself, I think I should be able to manage it. Should that not do it, I'll try and fit a fan over the third compartment, and failing that, I'm not against putting something like a CSXC-1 on the tank.

Either way, I'll definitely make sure that I have it under control before I stock even a clean up crew.

 

[Ranjib]

I cant think of a clear choice on housing. Both options has pros and cons.
Keeping the pi and relay board together will simplify things, no additional wiring, less wire. You can hide the pi's power adpater inside the housing. But this will make the housing size bigger.
Keeping the relay separate will allow changing the relay board independently of pi easier. AC and dc power will be separate , you can opt for different battery backup power for pi if you want. Sensors etc wiring will be different from the brain/pi. But this will involve additional wiring, extra wires. Currently, reef-pi 's relay control is straight from Pi's GPIO, hence we need 1 wire for each outlet plus two for power.

Because its a 29G I would probably go for a single bigger housing, with 8 channel relay. And a fairly big housing, that will be enough for recaptacles, pi, relay board, pca9685 breakout board (and may be some extra space for future ph/salinity/ato circuits etc.)

 

[Somnifac]

@Ranjib

The idea of having an AC and a DC side is appealing (I know that there would be 5V DC going to the relay board as well, but the power supply would be in the enclosure with the Pi itself).

I was actually considering using a VGA cable for comm between the brain box and the relay box. I bought an 8 relay board, so a 15 pin cable would be more than enough to handle control and power needs. If someone went all out with 16 relays, a 25 pin D-Sub cable would do them just fine as well.

 

[Katrina71]

We have the Jebao sw2 in our 8 gallon cube. I'd go with the 4 or even a dialed back 8 in your 29. Just my opinion. We have the 4 in our 29 Biocube.

 

[Somnifac]

We have the Jebao sw2 in our 8 gallon cube. I'd go with the 4 or even a dialed back 8 in your 29. Just my opinion. We have the 4 in our 29 Biocube.

Thanks for the tip. I will keep that in mind.

 

[Ranjib]

@Ranjib

The idea of having an AC and a DC side is appealing (I know that there would be 5V DC going to the relay board as well, but the power supply would be in the enclosure with the Pi itself).

I was actually considering using a VGA cable for comm between the brain box and the relay box. I bought an 8 relay board, so a 15 pin cable would be more than enough to handle control and power needs. If someone went all out with 16 relays, a 25 pin D-Sub cable would do them just fine as well.

Yeah vga cable will do, adafruit has even hdmi breakout board which can give 20 pin connection .
At some point in future I’ll add mcp2307 is multiplexer support, with that we should be able to avoid these wiring issues and most things can be connected just via a 4channel audio cable

 

[Ranjib]

We have the Jebao sw2 in our 8 gallon cube. I'd go with the 4 or even a dialed back 8 in your 29. Just my opinion. We have the 4 in our 29 Biocube.

Yeah, flow is critical. I have an mp10 which I got from raffle , if I get to choose it again I’ll go for two Koralia or jebao probably

 

[Somnifac]

Sat down and wired up my relay board my reef-pi, and after some self induced stupidity, it is working.

For those unaware, this will handle power distribution within my system. Each relay will be wired to control power to an outlet. The outlet can be manually switched, be on a timer, or it can react to a sensor (like temperature).

 

[Somnifac]

Still more work on the controller, rather than anything that's actually in the tank.

My PCA9685 board arrived yesterday. I got it connected it to the Pi and everything seems to be working fine. I can play with the level in the UI and read the change in voltage on the defined pins of the PCA9685 board. I'm still waiting for my transistors to arrive so I can wire up the 10V analog circuit that the lights will require for control.

I'm also thinking of grabbing one of these: https://www.amazon.com/gp/product/B01FE9EQ88 to make things easier. I'd prefer to not rely on single solderless wire connections to the GPIO headers, and this would give easy solder or screw terminals. Plus with just the relay and the PCA9685 board connected, I've used up both 5V pins on the Pi. The Pi-EzConnect (the thing in the link) would expand that and give me a place to power the Pi via the pins rather than the micro USB port (also a personal preference).

I'm also considering building an external chiller for some piece of mind. I've found a site that makes a solid aluminum waterblock that can accommodate a Peltier cooler on either side. From there, I can go to a heatsink on either side and probably get a couple of degrees of cooling. The Peltiers are 12v, and I can find a 12v pump to run it. The reef-pi controller could fire it up when it reaches a predefined temp, and cut it off when it reaches the target.

To put it into the system, I'm thinking of drilling and installing a bulkhead in the back of the tank, towards the bottom of the 1st and 3rd chambers. The intake would be in the 1st, output in the 3rd. Temp probe would go in the first so that the outlet didn't influence the temperature reading.

Thoughts?

 

[Ranjib]

Chiller is a good idea. I use fan which can easily bring down the temperature by 2-3 degrees.
That pi addon board is nice. I use perma proto boards from adafruit. You can use pca9685 board for 5v output as well, it has i2c pins on the other end for chaining, (1 5v, 1 GND, 1 sda , 1scl pin). I use the 5v and GND to connect to relay board.
There is a limit on how much current you can supply if you are powering the pi via GPIO. 2.5 amp unlikely to work for GPIO. MicroUSB based powering does not have that limit, something to remember.
I have never done any plumbing/drilling on the tank, so no clue on that side of things..

 

[Somnifac]

I've been doing more thinking, and not as much doing, the last week and had a thought:

I have a canister filter w/ built-in UV sterilization from my days keeping freshwater tanks. I was considering swapping the UV bulb out for a more "grow light" friendly spectrum and using it as a "chaeto reactor."

Anyone have any experience doing something like this?

 

[Somnifac]

So, I've been making slow and steady progress. I decided on going with one enclosure for my controller. After testing a 12v power supply feeding a 5v buck converter I found that they gave off far less heat than I expected. Maybe I'll need to put a fan opening in the lid, but that remains to be seen.

The enclosure is a 12x12 electrical junction box from Home Depot. I've been going at it with a drill to get the openings started, then finishing them out with a set of files. It's slow going, but the results are good. Once all non-round openings are done I can go ahead and start mounting the components that I have and wiring them up.

Things I still need to buy:

• Converter to convert 5v PWM control signal to whatever I need. There's a kit available that provided 8 channels of conversion from 5v PWM to most other control signals (5v analog, 10v analog, 10v PWM) via jumper configuration. This would be wired to the 12v power supply and the output of the PCA9685 board and be configured to output a 10v analog signal.
• Temp sensor.
• Lights. I'm sure I mentioned it, but I'll be going with a SBReefLight panel.

And I'm still seriously considering the canister filter as a Chaeto Reactor.

 

[Somnifac]

More work done on my controller. I bought an 80mm fan to mount in the cover of the enclosure, and controlled via PWM to ensure everything stays cool. I designed and had a mounting bracket 3D printed to house the fan in the cutout:

Since that seemed to work out so well, I'm starting a mounting plate for the panel mount components. The junction box I'm using is too thick for most standard panel mount items, so this is my way of getting around this:

reef-pi doesn't currently support everything, specifically the pH, Salinity, and ORP, but I made room for them for future expansion.

@Ranjib suggested an additional set of connections for dosing. I hadn't even considered that, but doing a dosing schedule of 2 part is probably a good idea.

 

[Ranjib]

For acros /sps it will be useful. DC pwm output in general will be useful to control anything from dosing pumps and dc power heads and returns. But you have like,...1 year if not more from tank being wet to acros/milis which will require two parts/intense light / high flow

 

[Somnifac]

Oh yeah, definitely. I'm taking the entire process slowly and deliberately. Nothing will go in until ready. I've had the tank for how long, and it's not even wet?

But I added 2 more jacks to control dosing. This would be able to handle 4 dosing channels if needed:

The worst case scenario is that it stays LPS and soft corals and I don't use the dosing functions.

 

[Somnifac]

Almost a big oversight, I'd forgotten a hole for the water level sensor for the ATO. So, slightly redesigned and added:

I would have been pretty upset if I'd forgotten that before printing it.

 

[Ranjib]

If we go with tentacle shield for ph/salinity the bnc probe holes will be determined that board