Filterless Tank

[EvilKen]

For some reason this really intrigues me. Having a tank that is almost self sufficient that works together to provide a thriving environment for both plants and fish using only the minimal amount of equipment necessary.

So, I was wondering what the potential downfalls are for not having a filter in the tank other than water current problems.

Thanks.

[Gomer]

magnus (on this forum) had a FILTERED tank with not enough circulation on one end. Added a powerhead an growth dramatically picked up.

Water circulation IMO is a big deal.

[Wasserpest]

Water circulation, as Gomer said, and mechanical filtration. Omitting the filter and placing a few cheap powerheads into the tank intrigued me too, but unless you enjoy watching floating debris (or have a fishless tank), you will need mechanical filtration.

I thought an understocked, heavily planted tank wouldn't have that problem, but I learned that one pretty large canister wasn't even sufficient to keep the water clear.

[Ugly Genius]

I ran a tank filterless for almost two months for very much the same reasons as you, EvilKen. Something about the simple elegance of plants and fish living symbiotically in a simple and hands-free tank appealled to me.

For the two months that I did have the tank running "Amish" (i.e. with as little technology as possible), I was quite pleased with it. The plants grew, albeit slowly, and the fish did well enough.

Then on a whim—also known as "impulse shopping"—I picked up a filter and slapped it on the tank. Plant growth exploded! In one week, plants grew at a rate that would have taken four or five times as long had the tank not had a filter.

Besides the slow growth, and assuming you are careful in the types of plants and fish you pick for your tank, I—and this is just me talking from experience and not from science or research—I don't think you'll have too many problems. Why not give it a shot? You only live once, right?

[Slaigar]

My 65g has only mechanical filtration(a sponge on a RIO pump). I have to say that tanks without much filtration are hard to start! Water movement is needed for most/all plants according to Kasselmann. I was reading her book and it does have interesting information on water movement. Some plants have high oxygen needs which cannot be met in stagnant waters. The lack of circulation will slow or stunt the growth of the plants.

[Hygro-Junkie]

an added fact is that some canister filters provide excellent co2 absorption rates for DIY'ers.

as mentioned, it is possible, but more desireable effects can be achieved with than without.

good thread!

[SCMurphy]

My ten gallon tank does not have a filter on it. When I slack off and the green water clears it is fairly pretty, if you like red plants.

[Wasserpest]

Originally Posted by SCMurphy

My ten gallon tank does not have a filter on it. When I slack off and the green water clears it is fairly pretty, if you like red plants.

Sean... I think you should mention that there are no fish in that tank.

[SCMurphy]

Originally Posted by Wasserpest

Sean... I think you should mention that there are no fish in that tank.

There are now, I got some small african tetras for it. However, it was a shrimp only tank for a long while. It's not going to be in that condition for much longer though, I'm changing over a bunch of tanks, getting bigger tanks and moving them around the room, and it is in that mix. However, in relation to plant growth benefitting from current, I don't dispute that, I actually agree. But this tank seems to break that rule, which is why I mentioned it.

[IUnknown]

I think filters just let you balance the tank easier. Security from when the plants are recovering from a major replant.