Cycling a Planted Tank.

[dikspence]

Hello,

As some of you may know I am in the middle of setting up a new 30gal Asian biotype tank. This tank will be home to 20-30 Harlequin Rasboras, a pair of Gouramis and 4-6 SAEs. A tenative plant list is as follows: Green Hygro (Hygrophila polysperma), Java fern (Microsorum pteropus), Watersprite (Ceratopteris thalictroides), Italian Val (Vallisneria spiralis).

I am interested in adding all of the Rasoras at the same time. If I "seed" the tank with filter media, plants, driftwood, gravel from other tanks would that be enough bacteria to support 30 fish or should I do a fishless cycle and if so would that harm the plants.

P.S. I know that the fish load sounds a little high but I have more than adequite filteration (Fluval 304) and I love the look of a big shoal of fish.

Thanks in advance for all your input.

[HOSStile]

Whether fishless or using borrowed media the most important thing to do is test, test, and test. Subjecting a tank to 30 new habitants is going to give you a nirite spike sometime, and the good bacteria may die waiting for a source of ammonia>nitrites >nitrates. I would suggest either cycling with a throw away or better still fishless with careful monitoring afterward.

[Garhan]

IMO for planted tanks I am not big on fishless cycles. In a 30 gallon use the seeded filter media from another tank and about 10 gallons of water to help it along. Let that stabalize for a week and then add your fish. You probably could add yopur fish sooner but if there is no rush, then give it a few days. I dont test my tanks except for PH, KH/Gh and that is it on start up and for 3-4 weeks. Then I dont bother as long as everything looks right.

Garhan

[Vallisneria]

Let that stabalize for a week and then add your fish

wouldn't a week without fish(ammonia) cause the bacteria in the seeded material to die off?

[AndyL]

Depending on the initial level of planting - often you wont even really need to cycle a planted tank.

With what you've mentioned, the water sprite and the Hygro will both greedily 'eat' the water borne ammonia produced by the fish.

But that said, you'd need to get the plants over their initial planting 'shock' and in many cases over the hump from emersed to submersed growth; but once they're set and established - they will be able to suck up a LOT of nutrients very quickly. Plants will generally take up NH3/4 before NO3, as it's easier for them to transform into useable nutrients (NO3 requires the plant to take a few extra steps to convert it to a useable source for them of NH3/4)

One would also need to be very careful at the rate with which one added fish - 1-2 small fish a week at most, the plants and very slowly emerging biofilter need time to 'catch up' to the extra nitrogen source.

If you're going to do it, get your tank running, add your plants - definitely wait a couple weeks for the plants to adapt - make sure they're growing at their best (You will absolutely HAVE to use CO2 injection - preferably presurized not DIY CO2) before adding fish. Otherwise you could risk one heck of an algae outbreak, and a lot of dead fish.

Andy

[Rainmaker69]

I, too, was under the immpession that the bacteria would begin to die shortly after there was no ammonia source added.

(edit) OK, simultanious typing.

[Rainmaker69]

Why is the CO2 so important?

[Garhan]

Carbon dioxide (CO2) is essential for photosynthesis. CO2 in the water comes from fish respiration, or is dissolved from the atmosphere. Just as you need to aerate and circulate water from the lower levels of the aquarium for oxygenation, you need to do the same so that the plants get enough CO2. The amount of dissolved CO2 is not proportional to the amount of dissolved 02. These two factors are independent of each other. Proper aeration and circulation of water will ensure that requirements for both gases are met.

Increased growth of aquatic plants may be realised by injecting CO2 from an external source. This type of injection provides a method of controlling the pH (acidity) of the aquarium water and providing the plants with extra CO2 to stimulate growth. CO2 may be injected from a liquefied source (gas cylinder) or by a small fermentation unit. The gas cylinder method requires a lot of hardware and is not recommended for a casual enthusiast. The fermentation method may be easily made as follows:

Take a 1.5 or 2 litre plastic cola bottle, poke a hole in the bottle cap and fix an airline tubing to it, making sure that this attachment is air tight. Half fill the bottle with water, and add 1/2 cup of sugar and 1/2 teaspoon of baking yeast. The mixture should be fermenting within hours. The gas generated during fermentation is fed through the air line to the aquarium and dissipated through an air stone. This will last about 15 days and you will need to discard it when the gas output visibly decreases, and mix up a new batch. Use a non-return valve on the air line to prevent the water from getting sucked back into the bottle. Do not fill the bottle more than half way, or you may end up with the yeast and sugar mix overflowing into your aquarium.

ACTUALLY USE oXQUOS DESIGHN.

GARHAN

[AndyL]

Why is the CO2 so important?

The simple answer is it's the macronutrient that you're not thinking of.

Without enough CO2 the plants can't metabolize enough Ammoni(a/um), basically you want the other macros in check (Phosphate, pottasium and CO2), so that the tank is Nitrogen poor. Thus once nitrogen is added (fish poop) it's almost immediately metabolized. Otherwise, you risk standard cycling problems, aggravated by algae.

Andy

[dikspence]

Thank you all for your infomative posts.

AndyL, I have also read that plants use NH3/4 before NO3. I was hoping that this would help my cause of adding most of the fish at once. I will be running a DIY CO2 system on this tank. Pressurized would be better but my budget doesn't allow for it right now.

The way that I am looking at the situation is this: Cycling a tank is important because it gives the bacteria time to grow on the filter media, substrate, plants, decorations, driftwood, etc. Plants in an aquarium also use up a large portion of fish waste (ammonia, nitrite, nitrate) in addition to the bacteria. I'm thinking that instead of waiting for the bacteria to grow by adding a few fish at a time I can just add it in at the beggining of the tanks life. Of course I cannot add the entire about of bacteria but if I maximize the amount of "stuff" from older, established tanks I hope to get enough to keep the fish healthy. The plants will also play a big role in this, which is why I am going to startup the tank the night of the edmonton auction which I hope to buy a bunch of large healthy plants. I also plan on adding filter media, driftwood, gravel, and plants from my other 2 tanks.