Adding Plants To A Cycling Tank

[JMcQueen]

Once my tank has finished cycling Im toying with the idea of adding some natural plants (probably Java fern on volcanic rock). My question is once I add it to a tank that has finished cycling, do I need to then continue to add ammonia (as opposed to adding fish) to ensure that the plants dont affect the cycling of the tank? Also, do you need to do anything to the plants before introducing them to the tank to avoid possibly damaging the bacteria balance etc?

I've always used artificial plants in the past so a little lost when it comes to the genuine thing.

 

[razer121]

adding plants is fine, im pretty sure they suck up the nitrate so if anything will help out, although im sure you wont need to worry about the parameters of the tank after adding them, they can only do good

some people wash plants in 10pts water 1pt bleach, although i can see it working i personaly just wash them in water and make sure they get a good wash before placing them into the tank

 

[JMcQueen]

I was concerned that just rinsing them under the tap might bring some chlorine into the tank and thus kill off some of the bacteria in the filter.

 

[razer121]

....i doubt it

 

[OldMan47]

Relax JMcQueen. An addition of live plants to a tank that has already cycled will not set you back at all. The plants have the ability to move some of your nitrates on to become plant food and disappear from the readings that you take. That is in no way harmful to what the fish will experience in your tank. They will have no idea what is keeping their water nice and clean. It will not matter at all if the reason is the planting or a fully functional biological filter. Either way, the fish see a condition of no ammonia and no nitrites. They will absolutely blossom in such an environment.

 

[JMcQueen]

OK cool, I might go speak to my LFS at the weekend and see how long it would take them to get me some in.

Is there anything else I need to be aware of such as plants removing oxygen from the water at night?

 

[JoshuaA]

plants removing oxygen from the water at night?

Plants produce Oxygen from the break down of Carbon Dioxide, that's why you should always have a few plants in your house to get rid of those stale farts .

Plants won't take in Carbon Dioxide during the night nor Produce Oxygen so as long as you have some surface agitation you will be fine. A lot of plants don't like fast flow or violent water flows either, so its best not to make the water surface like the north sea.

 

[JMcQueen]

I thought the cycle reversed at night with plants taking in oxygen?

"Respiration

Knowing that photosynthesis stops in the night raises the question about what is happening during those dark hours. Don’t forget that your aquarium plants usually have originated in the tropics where there is about twelve hours of daylight. During the other twelve hours the main process is respiration. This is in fact the opposite of photosynthesis. During darkness food substances are broken down (with the help of oxygen) and carbon dioxide is produced as a byproduct."

 

[JoshuaA]

I thought the cycle reversed at night with plants taking in oxygen?

That's news to me, I was always taught Photosynthesis stops at night due to the light no longer being strong enough to produce the energy it needed. It goes "dormant" so to speak but at night that's when it absorbs the water best. Plants always produce Oxygen and use the Carbon Dioxide for a Carbon source is what I was taught, It would seem counter productive to go the other way, reversing the plant has done throughout the day.

 

[JMcQueen]

This explains it better:

"Photosynthesis is the process by which plants convert carbon dioxide gas and water are converted with the help of light energy into glucose (energy) and oxygen gas. This process can be expressed in the equation:

6CO[sub]2[/sub] + 6H[sub]2[/sub]O + sunlight => C[sub]6[/sub]H[sub]12[/sub]O[sub]6[/sub] + 6O[sub]2[/sub]

Thus in an aquarium during the day, plants use the carbon dioxide, produced by fish, and water to produce oxygen and energy. The oxygen is used by fish for respiration. At night, there is no sunlight or artificial light for the plants to carry out photosynthesis, so the plants must rely on respiration to make energy.

So, plants take in oxygen and produce carbon dioxide. Because of nighttime plant respiration, the carbon dioxide level in an aquarium rises at night, but once the light is turned on, the carbon dioxide levels drop due to plant photosynthesis. "

I dare say provided you dont go massively overboard with plants, the amount of oxygen used isnt an issue

 

[JoshuaA]

Hmmm, So whats the equation for Oxygen > Carbon Dioxide? I'm not convinced, it's the first I've ever heard of it. The only reason I am aware that the Carbon Dioxide increase in a tank at night is because the plant stops using Carbon Dioxide and therefore the fish are just adding to the CO2 levels.

First I've ever heard of it being a cause for concern anyway.

 

[OldMan47]

Plants do indeed use oxygen at night and release CO2. The whole thought of a plant providing oxygen to a tank has been around since long before the internet. It is no more valid today than it was 50 years ago. A plant produces so little oxygen that it can in no way support your fish's needs. The fish get their oxygen as a result of gas exchange at the water's surface. When there is no light for photosynthesis, the plant goes on metabolizing and must have a source of oxygen. It gets that oxygen from the water column. On balance, a plant probably produces more oxygen in a day than it uses that night, but not by a huge amount.
The slight increase in total oxygen is why plants help maintain a breathable atmosphere for us oxygen consumers. We produce no oxygen and the only reason we never run out is that plants produce somewhat more oxygen than they use for respiration when light is not present.

 

[JoshuaA]

What levels of Ammonia/Nitrite will be too damaging for plants? Adding during a cycle could kill them? Or is the fact your lights are usually turned off?

 

[OldMan47]

Plants can thrive right through a cycle with its high levels of ammonia and nitrite. The reason we seldom recommend plants during a fishless cycle is that they require a strong light source. If you have a tank full of water with an excess of ammonia, plant food, and light, you get an outbreak of algae. Since all of us have had troubles from time to time with algae, none of us encourage a situation where algae is more likely. If you want to work on plants during your cycle and are comfortable dealing with probable algae outbreaks, go for it. It will not harm the plants or the cycle. If you go that way, mention the plants whenever you come seeking advice. that way, we can take the plants into consideration when deciding your best course of action.

 

[waterdrop]

Nicely said OM47. While the planted tank hobbyists may fuss a little that some plants will be sensitive to a 5ppm ammonia level, I think in the vast majority of cases the plants will come through just fine and often thrive, especially the hardy beginner plants that should be recommended for beginners. The algae problem in a cycling tank is definately the main story.

~~waterdrop~~