Is it possible to cycle a small tank?

[sparkyjoe]

OK, I've been reading a LOT of info on this forum as well as doing other research and I'm confused about the ability to cycle a tank under 5 gallons.

From what I understand, the ability of a tank to hold a stable cycle is directly dependent upon the amount of surface area in that tank on things like the substrate, decor and the filter. And from what I understand, the vast majority of the BB colonize in the filter.

So... A smaller tank may have less general surface area in the way of tank walls, substrate and decor, but if it has something like a sponge filter in it, and those are known for the amount of surface area they contain for the growth of BB, then wouldn't they be able to allow a smaller tank to establish and hold a stable cycle?

I honestly want to know 'cause I've been pondering this question for weeks.

I've got mostly 5 gallon tanks myself, and I prefer cycled tanks, but I'm running out of room and a 3-4 gallon tank might fit better in some places but I don't want to have to deal with multiple water changes each week.

[Mo]

Supposedly yes, a small tak can cycle. Bt becaus elf how unstable the water parameters will be. The cycle will be very difficult to establish and keep healthy

[wystearya]

One idea might be to get a sponge filter rated for a larger tank. It would take up more room, but it would be a good place to grow the beneficial bacteria.

Maybe you could try it and just see if it works? I assume you have a water test kit to keep track of the ammonia/nitrite/nitrate levels.

[sparkyjoe]

Yeah, I have a test kit.

I don't know that I'd want to try it with my betta boys, but I just got some cherry shrimps and thought of building them their own little deluxe home some day.

[Mo]

Maybe try it out with guppy fry?

[sparkyjoe]

Originally Posted by Mo

Maybe try it out with guppy fry?

Yeah, maybe... would Endler's work? Maybe just a fancy male guppy. I've been wondering about one of those too.

Hummmm, something to think about.

[Mo]

I would try endlers as they are hardier due to the minimal amount of inbreeding, compared to guppies

[sparkyjoe]

Yeah, that and I think they're smaller so less bio-load.

Fortunately I have someone in the area that raises Endler's as well as Fancy Guppies so I can get them without paying for shipping and probably at a slight discount.

[Mo]

Good to know! I would love to see the results! Everybody can definitely benefit from this experiment too.

[LittleBettaFish]

I think small tanks can hold a cycle if you use a filter with a high capacity for biological filtration. You need a disproportionate amount of beneficial bacteria to deal with the faster spikes of ammonia and nitrites.

This is why nano tanks with surprisingly high stocking levels also use canisters. Not only does it provide good circulation, but it also provides an enormous amount of surface area for BB to colonise.

I think utilising live plants is also key to stabilising a cycle in a small tank. They will help deal with excess nutrients in the water column and generally prevent any sudden spikes from occurring.

I think it would be harder maintaining anything under 2 gallons as it is just such a small body of water but 3-4 gallons should be able to manage it.