My Bachelor Thesis is based on creating a self-regulating Aquarium. Can you guys help me brainstorm a plan?

[jta117]

Hey guys, I really need your help. I am a mechanical engineer tasked with designing and configuring a self-regulating Saltwater Aquarium but unfortunately I know nothing about aquariums (Well, not true, ive been reading up a bit, but id still consider myself completely ignorant on the subject).

To clarify a bit more, right now I am still in the research phase and to be honest, I am not finding that much success, not that there isnt any information but for the fact, that I dont really know what exactly NEEDS to be regulated. Ive been brainstorming for almost an hour now after some basic reading about Saltwater aquariums and so far this is what Ive got.

Theory behind the Aquarium

• Parameters to control
• Water Quality
• Temperature of the room?
• Feeding
• Imbalances of the biological system
• Types of Saltwater Aquariums
• Water Filtration
• Biological Aspects behind the aquarium (e.g. Cycling a Saltwater Aquarium or Nitrogen Cycle)
• Sensitivity Analysis
• Size of the Aquarium and how that affects the parameters that need to be controlled.
• Light sources

For the first point (Parameters to control) Ive seen a couple of sites mention around 7 or 8 important parameters but those are all concerning the water. Is water really the only important thing that needs to be regulated in an Aquarium? The rest of the list, Ive been basically coming up with using common sense but I dont know how true they are. Can any aquarists here help me out with the brainstorming? A good question to prompt some good answers would be, for example, what do you do daily to your Aquarium? Literally anything you can think of, not just maintaining the water balance. and of course if youve got some other ideas, it would be immensely appreciated.

 

[PBnJOnWheat]

Hey guys, I really need your help. I am a mechanical engineer tasked with designing and configuring a self-regulating Saltwater Aquarium but unfortunately I know nothing about aquariums (Well, not true, ive been reading up a bit, but id still consider myself completely ignorant on the subject).

To clarify a bit more, right now I am still in the research phase and to be honest, I am not finding that much success, not that there isnt any information but for the fact, that I dont really know what exactly NEEDS to be regulated. Ive been brainstorming for almost an hour now after some basic reading about Saltwater aquariums and so far this is what Ive got.

Theory behind the Aquarium

• Parameters to control
• Water Quality
• Temperature of the room?
• Feeding
• Imbalances of the biological system
• Types of Saltwater Aquariums
• Water Filtration
• Biological Aspects behind the aquarium (e.g. Cycling a Saltwater Aquarium or Nitrogen Cycle)
• Sensitivity Analysis
• Size of the Aquarium and how that affects the parameters that need to be controlled.
• Light sources

For the first point (Parameters to control) Ive seen a couple of sites mention around 7 or 8 important parameters but those are all concerning the water. Is water really the only important thing that needs to be regulated in an Aquarium? The rest of the list, Ive been basically coming up with using common sense but I dont know how true they are. Can any aquarists here help me out with the brainstorming? A good question to prompt some good answers would be, for example, what do you do daily to your Aquarium? Literally anything you can think of, not just maintaining the water balance. and of course if youve got some other ideas, it would be immensely appreciated.

From my experience, the only things that make or break a reef tank, at least. Are the water parameters/quality and fish compatibility/disease. I would say PAR is important when it comes to lighting for corals, and temperature of the tank water. I think that’s all it really takes to be successful.

Most of those are solved through testing ie water quality say a trident Neptune system. Keeping water quality (I like calcium reactors and refugiums), ATO keep water coming back in due to evaporation. Then water heaters for the water and wave makers for flow.

 

[keithIHS]

Keep it as simple as you can get away with. Dont be afraid to be open and honest w your prof/advisor on the level of complexity that would garner an A...vs B. Dont worry about a "reef" tank. It'll be hard enough to just do fish.
By self-regulating aquarium I assume you mean self regulating aquarium system. A self regulating aquarium would completely closed like the sealed glass balls w a shrimp and bit of algae but that's a biology thesis not ME. A system allows for sensors controller and actuators.
You probably need to control temp and salinity (due to evaporation), maybe light. If you include automatic water changes using a commercial salt mix, that will take care of all of the other chemistry issues. Hint: if change 10% of the water per time period, w a given rate of pollution addition nutrient consumption, what is the steady state level of thepolutio

 

[keithIHS]

Keep it as simple as you can get away with. Dont be afraid to be open and honest w your prof/advisor on the level of complexity that would garner an A...vs B. Dont worry about a "reef" tank. It'll be hard enough to just do fish.
By self-regulating aquarium I assume you mean self regulating aquarium system. A self regulating aquarium would completely closed like the sealed glass balls w a shrimp and bit of algae but that's a biology thesis not ME. A system allows for sensors controller and actuators.
You probably need to control temp and salinity (due to evaporation), maybe light. If you include automatic water changes using a commercial salt mix, that will take care of all of the other chemistry issues. Hint: if change 10% of the water per time period, w a given rate of pollution addition nutrient consumption, what is the steady state level of thepolutio

Oops sorry hit post.
What's the steady state level of the polution or nutrient. Extend this to the diff eq for a continuous source sink in out of a reservoir. Do this for evaporation also.

 

[Stuartmercer]

If you are going with a 100% self-regulating reef then I would be careful with how complex it will be. There are so many factors that have to be controlled to keep a stable and succesful reef. If you are doing this, I would go with fish only rather than a reef (no coral) so water perameters arent as much as an issue, unless you absolutely have to do a reef.

 

[keithIHS]

OK. Now that I've knee-jerk my response, it's a good opportunity to re-read your question and actually attempt to begin answering it. Sorry.
You do need to "start with the end in mind", establish your requirements. This will drive your solution and its complexity. You need to figure out "types of saltwater aquariums". Fish only, easy inverts, difficult coral? 10 gal or 10000 gallon? Tropical, temperate?
Types of fish determine feeding. Some (maybe all?) under the right conditions dont need to be fed at all-they eat what reproduces in the tank. Almost always though fish are fed 1-5 times per day depending on the fish and inclination of the owner.
The whole nitrogen cycle is a startup issue and is best dealt naturally w bacteria. Once it's going you dont need to think about it except see nitrates below.
For a fish only tank, each day feed it, add fresh water and look at it to make sure nothing went wrong (including temperature-single biggest cause of failures)
For inverts each week check calcium, alkalinity, maybe pH.
For difficult corals, you'll need to add calcium and alkalinity probably daily and check magnesium, nitrate, and phosphate weekly and figure out a way to control those.
Take what I say w a big grain of salt. I'm a newbie at salt aquarium, but expert ME.
Go to the library and get a couple of books on saltwater aquaria. Google reefkeeping 101.
Keep it as simple as you possibly can. Do you have to actually set one up?

 

[58e970b2-3f88-4897-87ba-5]

What do you mean by self regulating?

Is the end goal an aquarium that you never touch? Just a tank with a bunch of machines doing all the “work” on it?

 

[WVNed]

My system is based on this

We call foam fractionators skimmers.
The biofilter can be various things too. Live rock, biomedia and filter media of various types.
Most of us manually check the essential chemical properties of our tanks and add calcium, alkalinity and magnesium trying to maintain a steady state value. Many use a dosing pump to do this. We also add other more trace elements this way.
There are some excellent articles in the reef chemistry forum on water parameters.
https://www.reef2reef.com/threads/o...-reef-aquarium-by-randy-holmes-farley.173563/

Think of the water as the blood of an organism. It transports the various components to where they need to go. Air, food and waste are the big ones.
Marine animals do pee in the pool all their lives so to speak. The pool has to be designed to remove it and bring fresh air and food to them at the same time. Many animals are photosynthetic. Their food is light and that has to be provided too in the proper type and amount.

What you are asking could easily fill several books and has. Sadly those books are hard to find now in many cases.

 

[keithIHS]

Correction: make it simpler than you think you should and in the unlikely event you have extra time you can add to it.
It's all about the water...and light for corals, algae, anemones, and other photosynthetic organisms.
Dont forget about oxygen and CO2. If you have lots of flow, only needed for coral or some types of filtration, gas exchange happens, but if low flow, you will need to do something about it.
Remember, you're not going to be graded on how well you understand aquaria but on how well you apply what you've been taught. Focus on the ME aspects: DiffEq, controls, thermo, heat transfer, maybe fluid mechanics (pipe flow and head loss), instrumentation, power, etc. Chemistry is important but it's not your area. Don't get bogged down by it. Chemistry is a great place to simplify.
Keep it simple.

 

[keithIHS]

WVNed's schematic is good for large aquaculture system or public aquarium. Most hobbyists use rock and sand inside the aquarium as biological filter and dont use ozone, UV, O2 concentrator.

 

[Mjl714]

Wow, you’ve come to the right place, lots of great minds and ideas here. Self sustaining is the base idea I try to apply when creating my reef environments. Ideally, this results in low maintenance and stability.

 

[Alexreefer]

There is a lot to know about aquariums, a fish only would simplify your thesis but it still is quite complex. Anywhere from parameters, filtration, and care. Without proper setup fish tanks could not possibly survive in our homes, everything from having to establish bacteria and biodiversity to the types of food we feed. There is lots to know, just ask and most people here are very experienced and could give you a definitive answer

 

[58e970b2-3f88-4897-87ba-5]

If you are looking for the simpler approach here is my little “tank”. It would be pretty easy to fully automate.
The things I control are lighting, flow, temperature, water quality, and food.

Lights are on a timer.

Flow is controlled by coral position and adjusting airflow and pump state. (On except when feeding)

Temperature is controlled with a heater on a controller. Issue is if ambient temperature gets above 23C in the room, the tank temp will also start rising.

Water quality is dealt with by changing out 100% of the water in the bottom jar (weekly). Occasionally I run a filter sock on the outlet into the bottom jar if water clarity is reduced (probably monthly).
I will also occasionally try to stir up anything that has settled to the bottom when running the filter sock.
Rock (bacteria) and algae provide primary filtration.
I also top off water to deal with evaporation (keep salinity stable)

Feeding is meatier food (brine shrimp) fed directly to the coral up top. Red Sea AB+ added to the tank for other coral.
Probably feeding a few times a week.

It should be fairly easy to almost fully automate a tank like this. The only thing I think would be problems are the filter sock and stirring up the bottom (maybe more pumps could help).
Feeding could be done on a dosing pump. The coral up top would probably be fine without being fed directly (likely just slower growth).
Also mixing fresh salt water up automatically would be nice.

Coral are Candy Cane Coral, Pulsing Xenia, Green Star Polyps. All considered good coral for starting out.

Creatures are Bristle Worms, Munnid Isopods, and Collonista Snails. All acquired as hitchhikers on the coral in there.

 

[Paul B]

How long does this tank have to last? Is it only for a few months? If it is, that is easy and you won't need to add anything except food. Can you get away with just fish, crabs, shrimp etc. and no corals?

If so, it is immensely more easy and as I said, you won't have to add anything but food. You can also use any light you like as fish can get by on light that you can see by and nothing special like spectrum, par, lumen s etc.

 

[keithIHS]

@58e970b2-3f88-4897-87ba-5 1st: love username and avatar.
Do you pump up from bottom to top? How do you control the siphon/drain?
Are you using plastic on bottom tank to reduce evaporation?
Maybe something like a Clarisea instead of socks. Magnetic stirrer for detritus?
Bubbler for gas exchange?
When you say "flow is controlled by coral position" do you mean you observe the coral position and you adjust direction and velocity of bubbler or other pump outlet?
-This is a fantastic example-
Can you list what params you are concerned about for water quality?
Salinity, Ca, Mg, alkalinity, pH, trace elements, nitrate, phosphate, organic and inorganic pollutants?

 

[EuphylliaAddict]

If it can be freshwater you could do this very simply with plants.

 

[elysics]

How long does this tank have to last? Is it only for a few months? If it is, that is easy and you won't need to add anything except food. Can you get away with just fish, crabs, shrimp etc. and no corals?

If so, it is immensely more easy and as I said, you won't have to add anything but food. You can also use any light you like as fish can get by on light that you can see by and nothing special like spectrum, par, lumen s etc.

The problem with that approach might be that it would be a bit too easy i would think. "I bought an auto feeder, a light, a jar and some inverts, put them together and nothing died" doesn't make for a very long or impressive thesis. Talking page after page about fine tuning amount of food and light by hand to the extent that you can see after 2, maybe 3 months might stray away too far from mechanical engineering and "regulating".

Most of the regulating doesn't have an impact yet at that early stage of a tank. You can do temperature control, control of the water level via top off, control of the salinity via up- and down-regulating automatic waterchanges, and then that's pretty much it aside from focusing hard on one particular piece of equipment or parameter like a skimmer that tunes itself or regulating ph by automatically changing lighting intensity and duration of an algae refugium to counterdisplay the display tank.

Inventing/testing a new filtration system or something like that would be a bit much for someone that is new to keeping an aquarium, not to mention that there wouldn't really be a way to tell if it really works or not in that short timeframe.

 

[keithIHS]

I recall a couple of my projects in undergrad were motivated by a collaboration between the prof and a company. The company was looking for out of the box ideas from a bunch of people that "didn't know better". Maybe some creativity and inventiveness would help with getting the A.

 

[jesspal]

Pick one aspect of reef keeping and how it can be self regulated. Then compare the results of a tank that is not self regulated, a third tank in which you do nothing and then compare the results.

 

[MikeTheNewbie]

Look for ReefPi and Neptune Apex for some inspiration although those systems are more aligned to electronics.
If you are looking for a mechanical project you might look at mastertronic for inspiration.