Does Excess light cause algae?

[shaman]

If I have a tank with slow growing plants, does excess light, > 3wpg cause algae?

[|squee|]

It will contribute indirectly, if you do not have enough slow-growing plants. Lack of plant growth = algae.

[hirowen]

From Tom Barr, algae depend more on lights and ammonia, whereas plant depend more on nutrient and CO2. What do you think?

[shaman]

Could anyone advice on what stop the growth of algae?
If plants are growing quick, there are still excess nutrients in water, same scenario as the case when plants are not growing? Thanks!

[hirowen]

hmmm..let me try..i guess the most effective way of stopping algae is to not offer them any light..in the case of planted tank, this gotta be ruled out. So back to circle, correct of dosing and CO2.

In CO2 enriched tank, excess of dosing (but of cuz not too much) is alright, so long that it is sufficient for plants to absorb. CO2 is impt part here, increase the CO2 to the highest level where ur fauna can take it.

In non CO2 tank, try to use lower wattage of light, maybe 1.5 ~ 2w/g. Little or no dosing is needed. Feed the fish more often and plant will take in nutrient from the excess fish food and waste.

From tom barr, a matured filtration system plays a part too as it will decrease ammonia efficiently.

[barmby]

Could anyone advice on what stop the growth of algae?
If plants are growing quick, there are still excess nutrients in water, same scenario as the case when plants are not growing? Thanks!

More CO2
More Plants
Less Fish

[shaman]

Hi bro, thanks for the replies.

I am just wondering why when plants grow well, algae doesnt grow? Is there's excess nutrients inside the water, why algae cannot absorb and grow?
What inhibit growth of algae?

[|squee|]

I don't think we know why for sure I think of it as one of Nature's laws.

However, if you think of ammonia as the primary cause of algae, you could say that timely removal of ammonia will prevent algae. Ammonia is much preferred by plants to nitrate when they need nitrogen, thus ammonia gets used up by growing plants when it's present. In the day, with the filter doing its job and plants actively taking up any present ammonia, algae is very disadvantaged. At night, the filter continues to remove ammonia. Although plants are no longer "sucking up" ammonia, lack of light still disadvantages algae to grow. This is how I see things, I may be wrong.

[shaman]

Thanks Terence!
Does plants absorb ammonia? I used to think that plants take nitrate

[PeterGwee]

Thanks Terence!
Does plants absorb ammonia? I used to think that plants take nitrate

Both. Plants in sheer mass will outcompete algae for the little NH3/NH4 produced.

Regards
Peter Gwee

[shaman]

Thanks Peter! So the whole idea is that ammonia is the culprit behind the whole algae disaster?

[|squee|]

That's the idea more or less. I recently discovered the cause for my staghorn algae on my moss... I removed the moss and discovered a whole lot of shrimp poo undetected by my water changes week after week. All the ammonia must have been crazy.

Also, in Diana Walstad's Ecology of the Planted Aquarium, she mentions that plants will take in ammonia first, before they take in nitrate. It's called preferred uptake or something, she showed a test where ammonia was being taken up even when high amounts of nitrate were in the water.