Fast growing replacement

[viejo]

Hello all.

I'm in the process of stablish a planted tank in a low-work profile. At the moment I'm just trying to reach an equilibrium between plants and fish to prevent algae and this kind of things. But the idea is, once the tank will be balanced, start to change some fast growing plants by medium/slow growing ones, to save pruning time.

My doubt is, supposing I'll be able to replace all my fast growing plants by an equivalent mass of slow growing ones, will algae have more chances to grow there?

I know plants and algae are fighting for nutrients in my tank, and fast growing plants prevent algae to boom. But once I'll have enough slow growing plants, those plants will keep algae under control or I will need to keep fast growing plants forever there?

(I'm sorry for the bad exposition of the question, I'm a bit limited in English, trying to improve everyday )

 

[VaughnH]

It will help in reasoning this out if you start with the idea that the plants and algae are not competing for the nutrients. Algae have no reason to compete for nutrients, since they need so little. And, plants don't have to compete with the algae, since what the algae consumes doesn't take anything to speak of away from the plants. Once you accept this, you can much more easily figure out the answer or probable answer to your question.

 

[viejo]

Then why everybody says: "to prevent algae in your new tank, add fast growing plants to it"?

Well... in any case, I need a big amount of plants to keep my tank in balance. If you say I must not worry about algae if I make this replacement (at the appropiate time, of course) keeping enough plants all time, I will be less worried

Thanks.

 

[VaughnH]

Algae start to grow, from the spores, when conditions in the tank are conducive to the algae being able to grow long enough to reproduce, as determined by what would happen if this were in a natural body of water, not an aquarium. In the natural bodies of water where algae evolved to survive and reproduce, those algae specimens that are most successful are those that start growth at opportune times. Those times would be when plants are not actively growing, so as to rob the algae of light. Some of the triggers that telll algae spores to start a growth cycle are ammonia in the water and low or fluctuating amounts of CO2 in the water. The reason for stuffing a new aquarium with a heavy planting of fast growing plants is to have enough plants growing that the water will never have any ammonia in it detectable by the algae spores, because the plants will consume it as fast as it appears. And, the reason to maintain a consistent concentration of CO2 in the water, every day, is to avoid a fluctuating or dropping CO2 level that algae spores can detect. It isn't a case of algae growing because there is a lot of food available to them, but a case of algae starting to grow because conditions are conducive to them being able to grow to their reproductive stage.

This is how I understand it.

 

[viejo]

I will think a bit about it, thanks again. I will start today to dose Excel to my plants. Not at the recommended amount, but a small piece of it. I want to grow the slow plants, not those foolish ceratopteris nor hygrophila