The Estimative Index Without Plants

[nry]

Just a thought, but would running an Estimative Index style of fertilising in a non-planted tank (I guess with CO2 but unsure?) prevent algae? It would certainly rule out aleopathy/healthy plant growth being the reason for reduced/no algae in an EI tank....

 

[jimbooo]

nice idea but IMO definatly not. the reason EI works is the plants are put in a luxury uptake situation so grow so vigourusly that they outcompete the algae for nutrients.

remove the plants and algae will use the nutrients. they wont go unused. if you think about it you will be replicating a non planted tank that has been neglected for ages with no water changes. high nitrate, phosphate etc....

in theory you will have a very sucessful algae farm.. it's not the nutrients that prevent algae it's the plants. tha nutrients just allow the plants to go into overdrive!

 

[Dave Spencer]

I can trigger algae through the presence of NH4, unstable/low CO2 and light.

If you have no NH4 and stable CO2, the other factor will be light levels. I wouldn`t know how low the levels need to be, but I suspect the stock lighting that comes with most tanks would be sufficiently low to not trigger algae.

The EI ferts added will not trigger the algae, so are largely irrelelvant, provided the above parameters are OK.

For me, the key with algae is knowing what triggers it. Unstable CO2 and the presence of NH4 could be a signal to algae of an unhealthy plant mass, giving it a window of opportunity.

It would be interesting to see what other people think.

Dave.

 

[nry]

But the whole point of EI is that nutrients are available at levels beyond that which plants need, noticeably so, leaving loads left in the tank whether you have plants or not?

 

[jimbooo]

hmmm. fair point,

where's mr barr when you need him lol.

 

[Dave Spencer]

But the whole point of EI is that nutrients are available at levels beyond that which plants need, noticeably so, leaving loads left in the tank whether you have plants or not?

That`s the point I was trying to make. Algae needs to be triggered, usually from poor CO2, NH4 or light levels. Dosing the water column with ferts can feed the algae, but it doesn`t cause it. I have tanks with nitrates at 25ppm and phosphates at 4ppm and no algae. On the other hand, I have grown algae in RO water with a purity of .002 microSiemens, just by adding sunlight.

For me, the nutrient levels are largely irrelevant and they do not cause algae. I think you could dose a plant free tank all you want and get no algae. Up the light levels and you will get algae.

Dave.

 

[jimbooo]

surely algae is always present in such a tank. i mean algae spores are everywhere, as dave says if you fill a glass with tap water and leave it on a windowsill it will eventually go green and you will see algae. simplistic i admit but if the same theory applies, fill a tank with tap water and do nothing apart from apply light (be that low levels if you like) and eventually algae will be seen. surely then if you were to add nutrients to that tap water then the algae will grow more quickly than if they had not been added. the level of light will effect the speed of growth but is not the cause of the algae.

sorry i tend to look at things from a more basic perspective than most on here but the way i see it is algae grows from an initial spore. that spore must be in the tank water in the first place or the glass/windowsill thing wouldn't happen. fluctuating co2 levels can not induce algae spores into the water therefore they cannot be the cause or trigger. all the things mentioned perviously either speed up or slow down algae growth. having plants in the water will reduce algae growth by using up the nutrients there so the algae cannot grow as efficiently. there will always be some algae in a tank be it at minute levels unless something is added or produced by plants to kill it. as you say it will not starve to death as an EI tank always has more nutrients than the plants need so there is always an excess present.

therefore if you add nutrients to a non plant tank then you will surely end up with more algae than if you had not added it.

please feel free to set me straight but i find it hard to see how any other result can occur.

 

[Dave Spencer]

surely algae is always present in such a tank.....

sorry i tend to look at things from a more basic perspective than most on here but the way i see it is algae grows from an initial spore. that spore must be in the tank water in the first place or the glass/windowsill thing wouldn't happen. fluctuating co2 levels can not induce algae spores into the water therefore they cannot be the cause or trigger.

You are right Jimboo, all our tanks have algae, I should have worded things a little better. What I am talking about is triggering an algae bloom, rather than producing algae in the first place.

However, like I say, I think the nutrient levels are irrelevant. How many people on TFF have fish only tanks with no plants, but high nitrates and phosphates. Not all of these tanks have algae outbreaks, basically due to the stability of their tanks. Create an instability from the triggers I have mentioned, and the algae spores you mention will bloom.

Dave.

EDIT: to reiterate my point, none of my tanks appear to have BBA or staghorn algae. All I have to do is leave the CO2 off for a day or two and I would be able to start a company up, exporting the stuff all over the world.

NRY: it is my belief that the EI ferts added to an unplanted tank will not increase the algae levels in isolation. The light levels some of us use in an EI tank would definitely cause algae

 

[nry]

Fluctuation of any nutrient (CO2 included) cannot create algae but from what I am aware of the fluctutation itself can trigger increased algae growth - this is why, as mentioned, leave CO2 off for a few days in an EI tank and algae will love you. Unsure specifically why this fluctuation itself is the trigger though?

 

[plantbrain]

No, it would not.

Something will grow if you have enough light, you have a choice of what that something is.
What do plants do to the system then?

They add O2.
They add chemicals/leachates
They remove nutrients
They remove NH4 pretty fast
They remove CO2

Regards,
Tom Barr

 

[nry]

Fair enough

 

[Dave Spencer]

Something will grow if you have enough light, you have a choice of what that something is.
What do plants do to the system then?

They add O2.
They add chemicals/leachates
They remove nutrients
They remove NH4 pretty fast
They remove CO2

I have read about you referring to the above, Tom, but I thought you were alluding to these as possible reasons, but with good reasoning. Are you surmising about these or are your convictions much stronger? Perhaps you have , or are in the process of conducting tests to verify this.

So, does it come down to the rate at which these parameters are being increased or decreased that indicate to algae when an opportunity to bloom is favorable? I would imagine keeping these rates of change constant will bring the necessary stability required to keep algae at bay as well.

If removing nutrients at a certain rate is an indicator of plant health, and therefore suppresses the algae, does having these nutrients present, but not being removed, act as a trigger for algae? I am thinking of an unplanted tank. I have thought that sufficient light would be needed to trigger algae in this scenario.

I know that algae can grow well in an environment with low nutrient levels and poor plant growth, where light levels should be high enough by default to trigger algae, but I thought that a high nutrient environment with insufficient light would not trigger algae.

What also strikes me is that as well as the rate at which these nutrients are being used, the quantity, as in turn over rate of N,K,P etc. will be a factor. One healthy, growing plant in a low nutrient tank will never suppress algae, whereas a large mass of healthy, growing plants in a high nutrient level tank will, hence the EI recommendation for significant substrate coverage of fast growers.

Adding chemicals/leachates could well be implying allelopathy in some form, or am I reading this incorrectly?

Dave.

 

[plantbrain]

I'm actually asking questions and suggesting a path to take.

Yes, you need enough light to start with. More light= more algae growth.

Adding chemicals/leachates could well be implying allelopathy in some form, or am I reading this incorrectly?

Yes, so how would you test for this?
If you look at allelopathic research(Oh my!), one of the methods used as a control is adding activated carbon to soak up any organics. Adding Activated Carbon to an aquarium would also be the control. So adding AC to a well run tank would remove this suppressing activity. and would induce algae if this hypothesis is correct. If not, then we can reject this idea.

It's been done and is easy to see.
No affect, actually the tank is better, not worse.


Regards,
Tom Barr

 

[Underwurlde]

Turn off CO2 = no plant growth = no nutrient uptake = light & nutrients all there for algae.

Must be the case... growth produces 'chemicals / leachates' = algae supressor.

Adding chemicals/leachates could well be implying allelopathy in some form, or am I reading this incorrectly?

Arrrrrrrrrrrrrrrrrrrrrrrrrgggggggggggggggggggggggggggggghhhhhhhhhhhhhhhhhhhhhhhh
hhhhhhhh

 

[Dave Spencer]

Turn off CO2 = no plant growth = no nutrient uptake = light & nutrients all there for algae.

I don`t think that removing the CO2 will cause a reduction in nutrient uptake that leads to algae. The fluctuation in CO2 causes the algae, and very quickly in my experience (read: cock up). Tom suggested earlier that the removal of CO2 by plants may have an effect on the system. Is it an indicator to algae of a less than desirable environment for them?

My belief is that the nutrient levels are irrelelvant in themselves, because I can grow algae in RO water, but I can`t trigger it by upping the dosing in my EI tank to double dosing.

Must be the case... growth produces 'chemicals / leachates' = algae supressor.

I am not sure that "must be" can be used. It seems like some good thinking, but not conclusive.

Arrrrrrrrrrrrrrrrrrrrrrrrrgggggggggggggggggggggggggggggghhhhhhhhhhhhhhhhhhhhhhhh
hhhhhhhh

Not sure about this one!

Dave.