Tropical Fish Forums

[fuzzimuzzi]

I'm probably leaving for further studies soon. But I want to leave some junk in my parents to contend with. Thinking of creating a self-sufficient tank. Somewhere along the lines of a 5x1.5x3 feet tank. If biology class serves me right, I need to create a complete ecosystem in the tank. So anyone got any ideas as to what plants, what fish and how to go about it? No feeding, no filters and no water changes. Just occasional addition of water. I know it is possible because some duo from university managed to create one. Help!

[schaadrak]

You need to read this book. It's not an entirely self-sufficient system as you still have to feed it, but it's pretty close. The author is a moderator on the "El Natural" forum on Aquatic Plant Central and would probably be happy to answer any questions or steer you in a certain direction.

Finding a way to set-up a tank that does not require inputs or maintenance will take a lot of tinkering. Probably months of trial and error experiments. A constant renewable food source is the first hurdle that comes to my mind. Coupled with inhabitants that keep populations in check without decimating their food-sources or overcrowding the tank.

Good luck. I know your not the first to try, or the last, but at least look into it and keep us posted as to any progress you make.

Tschuss,

Kent

[fuzzimuzzi]

have been doing some research...bouncing ideas off people...I've come to 2 realisation... harnessing algae's ability to grow is essential...and a plant that interacts with the air above the water may provide another channel for food to enter the tank's cycle...

generally, the plans pretty fuzzy. General cycle: Substrate to algae, algae to algae eater then to fish, fish craps goes to plants. The problem I have here is that I'd rather have some organism feeding off plants instead. But no plant grows fast enough without depleting the substrate...well...the only thing I know that spawns fast is guppies. hmmmm....

As a general direction, the tank would contain tetras, probably neons/cardinals, saiz factor, and maybe a betta or albino peacock cichlid just to get the tetras to school...

Anybody with a good idea for plants!!
p.s. thank God I didn't straight away started experimenting...discussing seems to be the smartest thing I've done so far in my "aqua"-life....

[fuzzimuzzi]

Just read some where that brine shrimps can breed every 4 days producing up to 300 of its own every once...hmmm...but the problem is that saltwater is recommended...is it possible in creating a section of the tank that allows the brine shrimps to hatch....since saltwater is denser and tends to resis movements...anybody know whether common aquarium salt for tropical tanks are also suitable?...brine shrimp eat micro-algae!! yay!!

[schaadrak]

Brine shrimp are just saltwater versions of fairy shrimp, which are found pretty much anywhere in the world. The problem comes from the fact that they're mostly vernal pool organisms, meaning they need a body of water that dries up as a part of their life cycle. I think there are a few that aren't, but they live in arctic conditions, not sure though. They are filter feeders, too, so in order to sustain them you'll need a lot of microscopic food floating around in your water column.

I'd lean more toward using scuds, snails, ghost shrimp and tubifex worms (I know they can be dirty, but not if you raise them seperate for a few generations) as scavangers and food sources, since they will readily reproduce in the tank. The trick is finding something that will eat them at the same rate as they can multiply, which depends on the size of your tank , the size of the population you start off with, available food, water quality, etc., etc...

As for your plant question, duckweed and/or salvina(sp?) will definitely grow like mad without depleting the soil since they're floating plants. And some fish like to eat them.

[schaadrak]

Another thing just occurred to me. Your going to have to import a lot of nutrients in the beginning, be it food or ferts, in order to sustain the cycle. Otherwise one small group is going to monopolize all of it while the rest of the system starves.

[Psyfalcon]

I've been considering something similar, as an experimental tank.

The problem is finding a small animal that eats plant matter and reproduces quickly. Eventually, it would all come into equilibrium, as the animal eats the plant, and produces waste, and young.

[fuzzimuzzi]

After much consideration and much teasing by fellow aquarist, I think trying to maintain to different water for brine shrimp, will result in a brakish. Which is not what I want. hmmm...plus brine shrimp can only live max 6 hours in fresh water...so that sort of defeats the idea....and water circulation would be a problem...but I do want to know...is water circulation crucial? if fish go all over the tank...then circulation generated by swimming fish is no problem right?

to schaadrak:I've checked out salvina and duckweed...brilliant...but it'll over power the tank...it'll block light from reaching the plants below them...and it seems that they are notorious for that...killing lakes and rivers...then again...some aquarist say that they just need abit of trimming... then it won't be self-sufficient anymore...

I was just thinking...maybe by placing tetras on top of the food chain...it be good...I heard it's difficult to get tetras to breed...but my friend told me he did it...and the secret is a thickly planted aquarium...so maybe a section of the aquarium would be stuffed with java moss or that sort...but java moss tends to catch mulm...is that bad?...it would facilitate the reproduction of microbs for frie feeding...right?

I just got ghost shrimp...someone told me that they are suppose to eat algae...so testing erm now...I'm going to my firends place this Monday I think...he has a self-sufficient tank...he said he's never fed the fish...but only added treated water...so I'm gonna document my trip there...and try to find the secret to that tank...dang I've a test coming in weeks time...

[Michael L.]

I read that endlers and snails are supposed to be great for this. The endlers reproduce quickly, as do the snails, and the endlers can eat the snails and some of their fry.

Another option would be shrimp. I would like to set up a tank like this for red cherries, but I have nowhere to do it in my house. RCS put out very little nitrogen and they hardly eat anything (it takes several hundred to eat an algae wafer in 12 hours). They also reproduce quickly.

I think tetras may be a bit messy for a delicate system like this. They are a little large and need to be kept in larger groups. Many of them will also only breed in tannin stained water, so if you cannot do water changes, the water will get very discoloured.
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[fuzzimuzzi]

Went to my friends place to check out his tank... about 5x2x3 feet... here are the pics:

http://picasaweb.google.com/limchengyee/Misc/photo#5044321213578539298
http://picasaweb.google.com/limchengyee/Misc/photo#5044321651665203506
http://picasaweb.google.com/limchengyee/Misc/photo#5044321986672652610

He has 4 goldfish. All healthy, their fins are full and no sign of roting. His tank has NO substrate!!... the ferns inside just grow...There's no snail no shrimp no algae eater...yet the water is clear enough see to the bottom... so cool... he doesn't feed them...that's way cool!!...

p.s. the ghost shrimp didn't survive the test. I guess they may eat algae...but they can't clear a half gallon tank full of free floating algae. I won't be coming to the forum for the next week or so. School tests starts tomorrow.