do I need a filter in a planted tank?

[sampster5000]

A filter is not neede but, yes, it creates circulation. People dont normally use carbon in planted tanks. In my 15 gallon I have an Aquaclear 50. It pushes the water to where it reaches the whole tank. I cant think of any dead spots that would currently exist in the tank. One important thing you can use in your filter is mechanical filtration like a sponge. I just use the Aquaclear filters sponge. Your plants will not completely absorb all ammonia, nitrite, and nitrates in your water. They do for sure consume the "nutrients" produced by fish waste but they do not remove it all. This is why I use Seachem's Matrix biological filter media. It removes things that plants cant by forming the beneficial bacteria on the media. Since I have shrimp in the tank, and had extra space in the filter, I added Seachem's Cuprisorb to remove any excess copper caused by the CSM+B (trace elements) because I have a lot of shrimp and snails and copper is very lethal to them.

The main thing is this... if you do not have a cycled tank, meaning the beneficial bacteria has formed in your tank, which normally happens in your filter, nitrates will build up insanely fast. This is why it is recommended that you completely change the water in a betta bowl, which has no filter, 100% every day. If your tank is not mega overstocked with plants and has high light and CO2 injection, and has a light bioload, you will need some filtration help. Eventually this bacteria will form on things in the tank, usually the gravel, but that can take a lot longer than it would in a filter where the water is constantly flowing.

you don't need an air pump in a planted tank, it's the opposite of what you want ... plants need CO2, not oxygen ...

you do want some water movement, but not surface agitation .... so consider a filter or a submerged pump to create some flow ...

Why he says this is because an air stone pushes the water up to the surface which causes the water to oxygenate and the CO2 to evaporate out. People like to use cannister filters because they can place the in and outflow under the water level to prevent loss of dissolved CO2. I would recommend an air stone being on overnight when the plants are absorbing oxygen and putting out CO2 because this will stun your fish and cause them to stop breathing which will quickly kill them.

if you have no fish in the tank, i think it might be a problem because the plants use fish waste for nutrients. somebody else should know better than me on this point though.

You can for sure have planted tanks with no fish or inverts. The poop from fish put out nutrients that plants can absorb but these nutrients are also held in popular fertilizers like KN03 and KH2PO4. Seachem sells Nitrogen, Phosphorus and Potassium and as you can see, these are held in... fish poo!

Anyone correct me if I'm wrong on anything here. Hope I helped. I'm still learning all of this stuff myself. It helps when you have a planted tank!

 

[Pyramid_Party]

I got a tank with a betta and african dwarf frog. No filtration and I have java ferns, java moss, and wisteria and they are growing fine. I do add a little liquid fertilizer though. SO I do not believe plants need filtration.

 

[Sab_Fan]

I would recommend an air stone being on overnight when the plants are absorbing oxygen and putting out CO2 because this will stun your fish and cause them to stop breathing which will quickly kill them. !

as an FYI, this is exactly what I do ... I have experienced a fish die-off due to overnight CO2 output in a planted tank, and it's not pretty ...

 

[jcardona1]

These are plenty examples of self-sustaining planted tanks with no filtration whatsoever. A densely planted tank will work as your biological filter provided you don't have a crazy bio load. While it can be done, I would still go with some sort of filtration, especially mechanical. A tank packed with fast growing plants will consume all the ammonia put out by fish waste and nitrates from decaying matter. I actually have to add a lot of nitrates to my tank 3x a week just to keep the plants happy

 

[dlobom]

you don't need an air pump in a planted tank, it's the opposite of what you want ... plants need CO2, not oxygen ...

you do want some water movement, but not surface agitation .... so consider a filter or a submerged pump to create some flow ...

there is plenty of CO2 in air, which is at most 30% oxygen

 

[Sab_Fan]

there is plenty of CO2 in air, which is at most 30% oxygen

and what, exactly, is your point, and how does it relate to aquaria?

as noted in an earlier post, using an airstone or other bubbler to increase surface agitation will generally cause an exchange of CO2 for oxygen ... and it is the CO2 that is important to the plants ...

so, there is no benefit to plants from added surface agitation ...

 

[DrownedFishonFire]

I actually have had tanks in the past with no air stone, no filteration whatsoever. And plants grew like weeds, no pun indeed. I think its more of luck on my part of the combination of plants I had in there.

 

[Juxtaroberto]

All you're keeping is plants and no fish? Then no, I'd say you don't need a filter, but you should get a powerhead to at least get water movement within the tank.

You'd also have to dose your plants with... everything. According to http://www.aquabotanic.com/plants_and_biological_filtration.htm, most aquatic plants prefer ammonia to nitrates, so you'd do good to dump in a tablespoon of ammonia in each day, to simulate the waste the fish would put out.

 

[sampster5000]

I actually have had tanks in the past with no air stone, no filteration whatsoever. And plants grew like weeds, no pun indeed. I think its more of luck on my part of the combination of plants I had in there.

In short, the purpose of the air stone is to prevent CO2 poisoning to fish. If you have no fish, this is not a problem as they will not use CO2 but instead use O2.

 

[GarNiac]

thanks for all the opinions,
this is a small tank that I'm currently working on, which is only 7g .
I put a filter in as I've recently added some more fishes, which are not shown on the photo yet, including hillstream loaches, oto catfish, snails, and more cherry shrimps. I plan to keep the tank simple, but its been torturing me trying to select kind of plants which would go in there. Well the green bits in the middle part is at least I could start with... Lighting is only 10 watt, not much.

pls let me know what do you guys think? and what kind of plants which would suit best for my little tank??
cheers