fishtank

[Silenti_etc]

The issue of suffocation in a space with greatly restricted area for gas exchange when using live plants:

There is a common myth about using live plants which comes about due to a simplifacation of biochemical processes inside of plant cells and their corosponding mitochondria and chloroplast organelles. That myth is that if you use live plants in an aquarium, those plants will eliminate the need for gas exchange by other methods (air stones, surface agitation and non-sealed off tops). Plants respiration (as due all other aerobic organisms) revolves around this chemical equation (and even here, this is a simplification there are many many more steps):

O2 [oxygen] + C6H12O6 [glucose - aka sugar] = H20 (water) + CO2 (carbon dioxide)

This process takes place in the mitochondria of a plant cell 24/7 365, in light or in dark.

Now with photosynthesis (again, this is simplified) this chemical reaction takes place in the chloroplasts in the presence of significant light reacting with the various pigments, of which the chlorophylls are the most present in green plants, to provide the energy nessecary to combine the first 2 reactants:

H20 + CO2 = C6H12O6 + O2

Also related to this topic is the misconception that a higher level of CO2 drives the level of O2 out of the water. The point at which this would even start to occur would be hundreds of times the CO2 or O2 toxicity level and would have to be done at emmense pressure to the solution due to gas laws and the laws of gas dilution in a liquid. Anyhow, I am getting away from my self here.

Coming back to the 2 chemical equations outlining resipration and photosynthesis...
While plants do take in CO2 and produce O2, they:
1) Only do so in the presence of a significant amount of light
2) Only do so when is respiring at a great enough rate to have extra energy to process (burn in respiration or store) the excess C6H12O6 produced by photosynthesis.
3) The O2 produced by photosynthesis is in an amount suffient to saturate all the O2 requirements of the plant. Plants only release excess O2.

At night, the plants will no longer adsorb CO2 and release O2, thereby drastically lowering O2 saturation of the water column at night. At a low KH (carbonate hardness, a measure of one type of pH buffering capacity of water), in some cases you may also run into problems of radical (read toxic) pH swings and CO2 toxicity. This is generally more the case when using a combination of high lighting (4+ watts per gallon normal flourescents, 3+ watts per gallon Power compact or Metal Halide lighting) high plant density, and direct CO2 addition to the water column even if using a CO2 canister with a pH controlled solenoid valve on the regulator.

And we are also leaving (no pun intended) out one major consumer of O2 and producer of CO2 in a healthy tank. Bacteria. One doesn't have to look past the denitrifying bacteria that should be near and dear to all fish keepers hearts. Look at what is going on in the 'nitrifaction process' also called the 'nitrogen cycle) It might be called something else in Canada and elsewhere, but you'll recognize it when you see it.

The common scenario goes like this:

Fish poop and any other organic nitrogen containing compound => broken down by various [oxygen consuming] bacteria into NH4 (ammonia, may also be NH3, depending on pH, not important to this discourse though). Fish also release 'urine' which is pure NH4, unlike humans for instance which convert NH4 into urea [(NH2)2CO2] in the liver inorder to store it in the body (NH4 is extremely toxic and can't be stored, fish constantly release NH4 through their gills.

NH4 gets broken down by another type of [O2 consuming due to respiration] bacteria and that very simplified equation goes like this:

NH4 + O2 = H2O + NO2 (nitrite) So at this step, you not only have the reaction of O2 with NH4 (thereby removing the O2 from the water) it all takes place inside a bacterium that uses an oxygen-based respiration.

The next step is basically a continuation of this process:

NO2 + O2 = NO3 (nitrate) again, same as above only a different type of bacteria is adding another oxygen to nitrite to make nitrate.

And in anaerobic pockets of a fish tank (usually inside rocks, deep in deep gravel/sand bed, places with extremely low to no water flow) you can have this going on in certain types of anaerobic bacteria:

NO3 = N2 (nitrogen gas) + O2 these cells then use this oxygen in non-respirational chemcial reactions.


The amount of O2 needed to process the food and wastes of an average healthy well-fed (not overfed) betta in a 6 gallon tank outweighs the O2 requirements of the betta itself. Also, massively planted tanks w/o careful control of light, nutrient supplimentation and other factors is bound for disaster. I have also never seen a longterm successful hermetically sealed mini-enviroment. Even Biosphere 2 didn't work out. And no, those little sealed off globes with the elodea and daphnia don't last more than a few months, even under optimum conditions.


In regards to the condensation caused by phasechange coolers (or even high powered TEC's I would assume):

These units typically produce condensation in an extremely specific location, namely the hoses leading up to the cooling 'block', and a small area around and behind the cooling block. An aquarium and its resultant rise in humidity, impellor created mist, and misc spills and splashes isnt so specifically localized. I am also under the impression, as I have no first hand experiance, that when using a phase change system, extensive efforts are made to prevent condensation. I believe most use neoprene in fairly thick layers on the hoses, around the CPU/GPU, and behind the CPU/GPU pcb. I also think many people use lots of die electric grease, silicone sealants and some more exotic materials to combat this very localized condensation. If you were suggesting that because people using phase change systems can deal with the problem, the solutions should hold a straight forward parallelism with dealing with condensation cause by an aquarium. I am not sure that covering every piece of electronics with neoprene, die electric grease or more exotic materials would really be feasible. How would you go about condensation proofing a optical drive? Can't use die electric grease on the laser and neoprene isnt going to work out very well either. Check with people who have experimented with spray painting mobo or pci or agp/pci-e cards. Many components get hot enough to melt/burn off the paint.


I hope this post made some sort of sense. If not, I'll be glad to review and make clarifications.

[Whisp]

As i mentioned earlier that can all be done in sealed canisters. You could easily put some seachem matrix in and have your bacteria colony. I already mentioned that earlier when i mentioned the filter media I am using on my tanks.

As for the drives You would only have to seal around the back end closest to the tank. You could still have the top open and if you seriusly wanted to could protect all drives. For example the scythe hdd silencer. that is made of rubber and foam and the drive gets sealed in with a heat pipe for helping with cooling. So all your hdd's can be protected. That item is located at scythe and called silent box. I had one and I know that no liquid would get to the drives.

As for the optical again you can seal off the hwhole back end. All wiring and connectors if done right could be protected in water cooling hosing but doubt you have to go that far. Just make sure any intake holes into itare sealed and on the front put a rubber seal if you really need be for where it open and closes.

As for the floppy drive that can be sealed too and some of the latest ones on the market are pretty sealed and not as open as before.

So that is your drives covered along with a hdd cooler.

Now for the motherboard you could put die eltric grease over it and water cool the system. Video card can be done with a fanless solotion and rest of componets dont have moving parts so just glob again the grease. Now you should have a couple fans for flow. As a note I kow many people on different forums and I didnt go search but they use 120mm fans and such to help with air flow across the top of te tank. Fans are cheap to replace too. Just think that with aregular tank you spend money on food, filter floss and any meds and fertilizer so whats a few extra bucks.

Power supply is the critical component and something I may consider putting seperate in its own box and make tghe system modular in the back plate or something.

I think it is only limited to your creativity. I have shown there a full working system protected agaisnt this environment.

Most I would see is some rust on some of the metal after years of use.

As a note to the power supply you could also do it now that I think of it since there are fanless of those too.

Video card could be water cooled too instead of a fanless unit but you may want to overclock a bit.

If all that is done you wouldnt even need a sealed aquarium environement.

So lets recap that.

1) you have sealed drives protected by silent box. http://www.scythe-usa.com/case/sbx/sbx.htm

2) watercooling system to cool nb, cpu and vga or fanless solution for nb and vga

3) sealed floppy and hard drives

4) fanless psu http://www.thermaltake.com/purepower...fanlesspfc.htm

5) all wires wrapped and sealed with tubing and heat shrink

6) mobo, vid and any other electronics covered in grease (note I have seen whole system cotaed with this stuff and still work. If we really wanted to go nuts we could just sit the system in mineral oil since no moving parts for the majority of the items and the drives are sealed.

Anyways that based on you saying need an open system. I am not going to argue that poiint since part of it is true however from what my local lfs told me you could have a sealed canister setup that would feed and monitor all that. Not cheap though. I personally wouldnt overclock but maybe a bit of vid and a slight cpu nothing major.

I would leave teh top of the system open. reason I said a cube system is because you could have one side the system and the other the aqurium. Im gues ing that would be in the 8 - 10 gallons and with teh right lighting wouldnt need a Co2 injection.

Again this is my opinion that it can be done with the right equipment and the cash to do it.

[Aero]

well, I believe it is possible, I think I read that the guys from Computer Modder maggazine did it once with some neon tetras. Not sure how well/long it workewd, they had only a quick mention of it.

[Silenti_etc]

Aero, that must have been the mention of using neon tetra's.

Whisp: Heck, I guess if you REALLY wanted to do this aquarium in a computer, you could always run the non-drive hardware in a submerged setup. Can't remember the chemical they used, but its non-conductive non-corrosive and you can submerge all pcb hardware (mobo, vids, sound cards, etc). That would prevent damage to those componants and use some kind of sealed box for the drives. If you want to start thinking exotic builds, you could always build a sealed off chamber on the top of the tank, sort of like a plastic hood (the kind with the flipup front) with ducts on 2 sides, one pushing air in the other sucking air out. Have a section of pvc fit rigged to hold a dessicant (with screen or both sides, or some sort of filter material). As the air flowed into the hood it would pick up humidity and any mist. As it flowed out, it would pass through this dessicant reactor, which would adsorb almost all the moisture. This would only have to flow ~10cfm or so to be really effective. This treated air could be routing inside the case as part of the cooling, or even directed at the cpu in a phase change system. This would probably eliminate most if not all of your condensation issues. Since dry air doesn't have water droplets in it.
I also believe doing this is going to be so impractical, we will never see anyone doing it. Like on of those ideas that is feasable on paper, but is impractical enough to bring to fruition that it will never be attempted.

I would also (for personal knowledge) challenge those lfs guys to produce (show you so you might show me) proof that such a product existed. Something like a catalog item, printed off the net, forum posts discussing the existance of said product.
I have found no proof anywhere of the existance of such a thing. And like i said, those globes with elodea and daphnia I see at some 'nature gadget' shops don't last more than a few months before crashing.

Aero: There is a difference between putting fish in a water cooling reservior and saying you successfully incorperated fish into a water cooling setup. As I recall, those guys didn't keep those fish alive for more than a week or so.

[Whisp]

Yeah the so called liquid you are refering to I already reffered to in my post above.

"6) mobo, vid and any other electronics covered in grease (note I have seen whole system cotaed with this stuff and still work. If we really wanted to go nuts we could just sit the system in mineral oil since no moving parts for the majority of the items and the drives are sealed."

It was my number 6 where I mentioned mineral oil. As for the drives I also mentioned a sealed container which is silent box from scythe. I had one so know exactly what i am talking about when it comes to that item and how its made.

The grease though will do the job and you dont have to submerse and everything can be coated for protection. So that stuff you mentioned for that device is unneeded since i already specified how all parts can be protected

as for the sealed filtration systemim talking like the items from pentair aquatics where you attach a submerible pump for the intake and you can add as many canisters as you want with different configurations along with adding a Co2 dispensing item if needed. Also have uv filtration and anything else since the canisters can be filled with the filter media of your choice including bio media. There is also the fluidized bed filters.

With todays technology I think this is more then possible and again I will point to my thread above of how you would seal off all the parts in which they will be protected.

Also note the scythe hdd cooler isnt that expensive. I sold one for like 25 bucks cdn I think. For the cdrom some rubber tape or some sealer will do the job along with the floppy. If needed could seal on rubber and foam over the back where open elctronics are for the ports. Even fans can be protected by putting grease on their little chip for the motor and the fan should be oiled anyways for the magnet and motor. Vid card sound card can totally be coated along with motherboard and if watyercooling no moving parts. Psu if fanless could be covered in grease too.

Anywyas I am just repeating myself but my point is that type of protection of your system could be done for cheap. Most likely the aquraium items would be a little money but if you do that dont have to worry about fancy filtration system. Probabaly just needa chiller.