700ml (0.2G) 3D Printed Pico Reef

[Polymate3D]

Hello everyone

I previously made a couple of threads on the development process of this, but now it is time to start it up!

This is a 700ml pico reef. Yes you read right. A bit more than a personal coca cola bottle of water.

Heating:

Heating is being done through my own design PCB and controlled with a ATtiny13 micro controller:

The board runs off a 5V, 2.1A USB plug, so very universal across the globe. The heating it done through these 2 heatsinks on 2 banks. These 2 banks are PWM controlled so I can adjust the heating amount in a very granular way to help stablise temperature. This in code is a ongoing development but already we are staying within 1.5c window. This version of the board can deliver up to 4.8W of heating, but a later version should push this up to 9W for bigger builds which is the intention. In testing this can deliver +7c over ambient in this build.

Cooling:

Cooling is to be fitted onto the back but it is a small TEC with 40mm fan. This again is controlled by the micro controller and can consume around 5W of power at maximum. Taking inefficiencies and temperature delta, around 2.5W of cooling can be delivered, or around -4c over ambient.

This method is being used along with a 3D Printed tight sealing lid to remove the evaporation issues with pico reef aquariums.

Pump:

The pump is another 3D printed part of this build. It has a 3D printed impeller and housing. The DC motor is fitted into the lid of the aquarium, and there is a 3D printed shaft which goes down and is part of the impeller itself. Here is a render of an earlier version:

The DC pump is also controlled by the micro controller, and will allow me to make it work in version modes. Currently is changes from a slower mode to a faster mode every 3 seconds.

The motor is small but very powerful as can be seen here on 100% power:


and then how I am currently using it:


Will likely tone down a bit more. The pump is just that for now, but there is a screw thread to add filter media and carbon possibly later on. I may also fit a overide switch so the full power can be used briefly to whisk up detritus prior to a water change.

LED Lighting:

Lighting is done by a single 1W 25K LED which is fitted with a lens to protect it and is running at just 0.5W.

I have tested this with my Seneye Reef and PAR levels are the following in the middle (Because the seneye reef is as big as the aquarium!)

Bottom = 65 PAR
4cm up = 105 PAR
7cm up = 232 PAR

So very small, but very suited for the application. The LED is not controlled by the micro controller and runs off it's own USB cable so you can get a USB timer to control that aspect of the aquarium.

Inhabitants:

The water and things inside where taken from a established aquarium. These are:

3 Amphipods
Cheatomorpha
Frag plug with some GSP

The GSP was being covered by hair algae, so I have cleaned it up a bit and will see if it settles or not.

Got much more I could discuss, but leave that for another time or if anyone has any questions. The idea is for this to be a easy and cheap Pico Reef that is actually fairly low maintenance eg:

Low / No water evaporation
High tolerance of water temperature for both heating and cooling
Varying pump to stop dead spots

Thanks for taking a look, and I will update good or bad as things go. The code running the micro controller has been used for 3 days, so it will definitely still need work, but this will be as it goes so it is being tested as well.

- Paul

 

[Devaji]

Dude that is cool.

 

[Gumbies R Us]

Following along!

 

[Polymate3D]

Thanks for following and the kind comments!

Today it has just been running along. Been keeping an eye on temperature and it has stayed between 26.3c to 26.8c all day. Bit on the high side so will change that but temperature control already pretty good. Very little overshoot (+0.2c).

GSP still have the hair algae on it and not happy but a couple of polyps came out today. The amphipods are scurrying around like they do.

I'm debating currently what to try and put in here. My LFS have these tiny red legs hermits, about 1cm including shell, and also bumblebee snails. My current thinking is they may world but also a sexy shrimp may do as well.

I debated a tiny goby like in the PNW tanks like @Biota_Marine also agreed can work, but this is 10cm in all directions. Not with a 14cm length, so I'm not sure it's viable or fair.

I would like to note any inhabitants try have a Fluval Flex 34L in the next room awaiting them at any time.

Will find some sand floor and print a 3D printed rock as well soon.

If you have any ideas what to else I could try including corals, please let me know!

 

[Polymate3D]

Minor Update.

The aquarium has been going for over 4 full days. Temperature is staying at 26c +/-0.3c so far across all 4 days, so really encouraging results on temperature control of such a small volume of water.

The GSP which is in the aquarium and was covered in hair algae is starting to come out and is getting back a hint of green. The mother colony and this one are currently in my quarantine tank with a Fluval EVO light and not super happy, so its good to see this piece under my own light setup is looking better.

Amphipods are also happy crawling about including within the 3D printed 'rock'.


Power consumption on such a small aquarium is equally small, with a average of 60<64Wh consumed per day. This is for the heating, lighting and flow of the aquarium. Works out to around £0.55 a month here in the UK to run.

Looking at power also shows the heating aspect is very regular when needed.

You can see in the evening is heated the aquarium less, and this matches when my laptop was setup on the same table. Just shows how sensitive this volume of water is and how important this part of the aquarium is.

 

[Polymate3D]

Hey everyone

Went to LFS and got a sexy shrimp and 2 small pieces of Kenya tree. 1 brown, 1 green.

I will find some sand I like soon and then replace the 3D printed rock with something else better suited.

Here is how it is looking:

GSP also continues to show signs of improving, so the light is looking like a good candidate.

So still more to do, but it's going well.

- Paul

 

[Polymate3D]

Update - Day 11

Hello everyone

We definitely have some algae now. There is a little bumblebee snail in this but hiding at the back. The GSP is doing okay, and the Kenya Tree goes from being super happy to sulking.

I decided to do a water change of 50% today and use the older water to do some water tests so we can see what is happening after a week running with livestock in there:

Salinity = 1.025
PH = 8.0
Ammonia = 0
Nitrite = 0
Nitrate = 10
Phosphate = 0.02
Alkalinity = 9

There is no carbon in there so I think there could be toxins from soft coral warfare going on it such a small aquarium, so I am considering carbon in a bag or as a substrate even. Worse case with the later I just flush it out.

Temperature still holding well too, so still going to plan. The lid is doing a super good job at stopping evaporation which is great to see.

As always, any questions etc, please feel free to post and ask away.

- Paul

 

[Polymate3D]

Update - Day 17

Bumblebee snail and Sexy Shrimp seem happy. GSP is out and also showing some new polyps, so that promising. The Kenya trees. Brown one is opening up and happier. Green still sulking and not losing colour.

The cooling side has been worked hard this week here in the UK and it works but the transistor powering it gets super hot, so a revised board will use a MOSFET instead for this area. I have some a little bit of air cooling and evaporating to give the transistor a break and adding around 10ml of RO water at night to top the loss up.

Otherwise ticking along well. But more algae so bumblebee snail doesn't seem to keep up. May look at a stomella snail or something else. Added a little bit of carbon which is currently acting as a substrate. Easy to get back out.

So far, very little needs to be changed to the controller design to get this performing as desired. A new PCB is on the way to test a dual LED setup, and then a final (hopefully) PCB will have the MOSFET for the cooling to make that a 24/7 option if required. May be nice for a larger pico with a catalina goby!

- Paul

 

[AlyciaMarie]

This is looking awesome! I never thought of a peppermint shrimp in a pico, but that's a great idea.

Edit: Sexy Shrimp

 

[Polymate3D]

This is looking awesome! I never thought of a peppermint shrimp in a pico, but that's a great idea.

Thanks!

The little Sexy Shrimp so far seems right at home in there. I tried a small hermit crab but he devoured everything in 1 day and I was concerned about how much I would need to feed him. Hope your 40oz develops nicely.

- Paul

 

[Polymate3D]

Day 20 - Disaster!

Woke up to this morning to the aquarium at 37.4c (99.3f). Everything inside looks to have gone unfortunately, but the aquarium is already back down to 27c. Will see of any life as the day goes on.

This test aquarium has been in the kitchen and the thermistor detecting temperature was taped to the back of the tank. It looks like my interested 4 year old has touched this and pulled the thermistor out. Placing it back in, the cooling kicks straight in. The final version now will also be soldered to the thermistor and a thicker wire with many strands.

The final build was to have this covered from any tampering with, but alas it has causes me this loss. Without this connection it would of been running blind.

So I am rather sad today, but things will move on. I may do 0.7L again or the bigger 2.5L, but it will be started again properly by the end of the week. I have a new 3D printed rock, and a interim control board which resolves some of this original ones issues. I have also finalised yet another board but that will take a while to turn up.

So sorry for this bad update. The thermistor in this build was always a bit fragile, but hands also reaching it was completely avoidable by myself. Will be back with an update on the 2 circuit boards before the aquarium is setup again with a test frag and likely a cheaper inhabitant than a sexy shrimp.

- Paul

 

[VintageReefer]

Hang in there. This was working great. No product goes start to finish without a few revisions. It will be better in the end this way

 

[Polymate3D]

Hang in there. This was working great. No product goes start to finish without a few revisions. It will be better in the end this way

Thanks. I am not easily deterred if I can see how to improve or fix what happened, so it will continue on.

The current thermistors were fitted into Dupont headers but it is not a tight fit. The leads of the thermistor also are close coming out the same side, so the new ones will be a glass bead thermistor that's axial and I will solder and shrink tube the joint.

The interim board turned up today which should reduce the load on the transistors, but doesn't fix the cooling side. Have to wait a couple of weeks for that.

I also took the pump apart to check the motors metal shaft. No signs of rust, salt creep or even liquid. The design makes sure it stays dry and covered by the 3D printed parts.

Will repost once I have tested the new board.

I'm excited to get and show the board I am waiting for!

- Paul

 

[Polymate3D]

Take 2 - Day 1

So the little 0.7L aquarium has been reset and the thermistor now soldered and fitted to the back of the same aquarium. I originally intended to run the Interim control board, but have opted for using the same one for a few reasons:

(1) I intend to use a bigger container. I have to in mind. 1 is 1.7L and the other is 2.5L
(2) This board has the fan at least for cooling if things get really bad again this summer.
(3) I can update the micro controllers code to try and improve things

So with this in mind, this board will live, breath and die on this specific 0.7L aquarium. I will leave the next post to talk more on the other boards incoming.

So back to this aquarium. It has a gravel floor from a established aquarium and a new 3D printed rock. This one contains a total of 6 holes for coral frags. Currently the following has been put in:

2 Kenya Trees
Blue mini Cloves
Grimace Play Polyp
Small Toadstool

I will add some sort of invert to the aquarium once algae grows and the aquarium needs it. There is also a small piece of deadmans finger macroalgae.

3D Printed pump, LED light etc are all exactly the same as before.

The next update will be about the Interim board and hopefully the final board.

- Paul

 

[Mr Fishface]

This is the coolest tank I've ever seen. I'm so glad to see you restarted after that tragedy! Can't wait to see how it goes!

 

[Polymate3D]

Interim Board

The Interim board was a quickly made design to overcome pushing the transistors so hard. It spreads the heating aspect over 3 transistors instead of 2 and reduces the heating capability from 5W down to 4W. The heatsink is also increased from 9.7cm2 surface area to 16cm2 surface area which should result in almost half the peak temperature rise.

The heating over the 3 transistors can also be controlled very well and so I can determine what the maximum dissipation is for this size heatsink that I am comfortable with using(Anything below a skin burning temperature. I want to be able to hold it without burning myself).

Cooling was not resolved on this board, as I was still trying to understand how to do this in a way I felt would work well long term.

This board does however have lighting added in the form of 2 LED's. The current control is on board so just wire up the LED's. This should enable me to use it on a larger container, which is how it will be used. Anything learnt will be adapted to the 0.7L aquarium, including moving to this board if there are enough advantages.

This board will also be used long term to experiment with 3D printed DC Pumps and the wavemaker functions it can produce with them, so I am investigate this more.

- Paul

 

[Polymate3D]

This is the coolest tank I've ever seen. I'm so glad to see you restarted after that tragedy! Can't wait to see how it goes!

Thanks for the encouragement!

I don't plan on dropping the work on these pico's easily as I want to produce a system for up to 5L aquariums that can run from a USB plug (5V, 2.1A) and make pico aquariums easier and cost effective.

We shall see how this goes, and as the new boards come in and get tested on various sizes, I will be able to learn and improve them.

- Paul

 

[Polymate3D]

AIO Board

So the Interim board is being made up and the aquariums so far is performing as it was previously, so no issues. The more comprehensive end target board is now shipped and so should only be a couple of weeks away:

The AIO board is designed to control all aspects I need in a single board, whilst still sticking to the 5V, 2.1A USB powered target. It is designed for use up to 5L aquariums, and if successful will become the foundations to a much more capable board for small nano aquariums as well.

The AIO board changes multiple things so I will cover each aspect 1 by 1.

Pump

The DC Pump is now a fixed speed and not controlled by the controller (Interim will continue those experiments).
There will be a override switch to enable full speed on the pump prior to water changes, and there is also a 'tweak' option on the board. This will allow a resistor to be fitted to change the pumps speed. Each aquarium size will have its pump design altered to work well with this.

Heating

Heating is increased from the 4<5W previously up to 7.5W. These will have a heatsink on top and also a 40mm fan which will be connected on the header 'H_FAN'. This should reduce peak temperatures but more importantly, improve thermal heat transfer which should stabilise temperatures even more. Current is +/-0.3c.

In the event of a temperature drop below 23c (Target is 25.5c) the LED lighting will be overridden to be turned on. Each LED has its own resistor controlling current and when on, can generate up to 0.4W of heat each, or 1.2W for all 3 LED's. This increases the 7.5W up to 8.7W.

Cooling

Cooling should work correctly this time with a Peltier element, heatsink & 40mm fan. Rated at 5V, it should have a cooling capacity of around 3w which should be enough for a -2c or -3c temperature drop over ambient temperature with NO EVAPORATION of water.

Lighting

This AIO board increases LED support from 2 LED's to 3 LED's, plus a add on header. This header can be seperately powered to enable more LED lighting. The maximum this board will do natively is 1.8W (0.6W * 3). The current 0.7L aquarium is achieving a average of 105 PAR with 0.5W, so this should cover most uses, but something like the 5L aquarium planned may require the extra power.

The Lighting will be controlled by default like a LDR (Light detecting resistor). This will detect ambient room light and kick the lighting on. Internally the micro controller will then track the time period it is on for, and close off after a pre determined value in the code (Initial will be 10 hours).

On top of this there will be 2 switches to force a LED OFF mode or LED ON mode, in case you need to override this.

 

[Polymate3D]

Take 2 - Day 6

Kenya trees are loving life. Toadstool is on the floor but seems happy. Paly still not happy but opens time to time.

Temperature stability like before with +/- 0.3c from 26.0c.

New boards have landed here in the UK so will hopefully have them within a week. For now this tiny tank just kind of works.


I placed another smaller crab in and he kind of bashes things about but I think with a different rock we can probably make it work.

I have 3 size aquariums for the next Pico to test the control boards:

IKEA 1.7L 365 Jar

2.5L 15cm cube aquarium

5.0L 18cm cube aquarium

Want to post your opinion on what to go for. Please vote in the poll here:

Which Pico size next?

 

[Polymate3D]

Take 2 - Day 19

Little 0.7L pico is running well. 2 Kenya Trees are doing well, as are the blue cloves and the toadstool. The palys are opening up but still not super happy. Also added another addition after the little piece of leptoseris didn't make it.

Looks more like Cyano than algae growth, so will start putting a few drops of phyto in there as a food source. Otherwise it is just working. I turn the light on and off and thats about it. Will do a water change soon, but being at 20 days now, I may just do it on exactly 1 month.

In other news, the MOSFET based board is here, so next post will detail more on how that is doing.

- Paul