I'm gulity of this mistake. Hence let "loose fertilisers" refer to KNO3, KH2PO4 and traces. Or "EI ferts" sound more correct, since most who use the above 3 chemicals dose the EI way?

Hmmm, "Loose ferts" sounds good.  I'll start using that from now on.

But it is not used exclusively for EI. What about the PPS method that is currently one of the popular methods over at APC?

And we're not talking about those 3 ferts. There are others like epsom salts, calcium nitrate, potassium sulpahte, calcium chloride, and much more.

Trace mix is trace mix.
PPS still does the basic 3 and if you look at EI, I address CO2, lighting and GH, which deals with Ca, Mg and SO4.

They both add the _same things_.
You can use some standard solution or dose the ferts dry, your subtle accuracy improvement will make no difference doing dry dosing vs liquids.

If you chose either testing or not, you need to make sure the CO2 is in a good range and this is far more difficult and troublesome than any fert routine and far more significant in terms of problems and plant health.

Regards,
Tom Barr

Quot "
...That paper by Sears and Conlin gave major insight into the fertilisation of planted tanks, and is an important foundation to the evolution of many, if not all, modern planted tank fertilisation methodologies and theories."

I kinda disagree to Vinz's intro here. Before Sears & Conlin there were already other pioneers spear-headed the studies of planted aquarium and developed into commercial products (although pricey). For example founders of Dupla : Kaspar Horst and Horst E. Kipper in their book "The Optimum Auqarium" (I had a copy published in 1985) already introduced undergravel heating, trace elements dosing - the effect of chelated iron to water plant, macro nutrients, and most importantly the use of CO2 gas with closed loop PH controller to promote plant growth ! (In Sinagpore I first learnt the Dupla system way back to 1990).
But I do agree that Sears & Conlin and many others brought these "commercial secret recipes" into light and with the power of the internet the knowledge had been reaching to the global planted aquarium enthusiasts ever since.
Cable heating is Dupla's idea and they can certainly have it right back.
It's never been shown to help fior the reasons speculated in practical nor any research.

They never made any macro nutrients(NPK) for many years, it was assumed that fish supply all that's needed. They claim they are responsible for trace dosing, that had been done in the research for a long time prior, same with CO2, they just brought it over to the hobby and charged an arm and leg for their stuff.

But the main thing they did was bring CO2 into the hobby, not macro nutrient dosing. Soil substrates, hoagland's solution etc have been used as macro sources for 70 years or more.
PMDD did bring the NO3, K+ dosing to the forefront in an effect to limit PO4 which was assumed to cause algae.

A mistake that Dupla and many other companies also made.

I have no idea why they, nor any of the other companies did not try and show that PO4 caused algae or not.

I added it, I never had algae.
Looking back at what really was significant and being able to tease apart which elements where significant is relative today.

But cables, ph controllers, PO4 limitation, NO3 limitation, Fe limitation etc are not particularly useful ideas today........practical experiences quickly tell you this.

I'm always amazed at how someone can be goign along dosing nutrients with good plant growth, have a 2ppm PO4 level, then when they get algae, they blame the PO4.

They did not have algae before they had the high PO4.
But they often only test when something goes wrong, notm leading up to it nor ever induce a possible problem on purpose.

You never learn causation this way.
And few of the companies seem to have done this.
But they don't care so much about that as they do about being a business and making $$.

Paul and Kevin and myself are not selling you something.

Regards,
Tom Barr

Hi Tom

I guess my data on Dupla was wrong then. Thanks for pointing out.

One question to seek your comment : You brought up the point that the older thoughts on "limiting theory" (PO4, NO3, Fe,...etc) of curbing algae did not hold ground today : as many had experimented high dosing of these and only good plant growth and not algae. What is holding back the algae ? Could it be the strong growthing plants releasing defensive chemical against algae ? Or highly oxygenated water deter alage to set foot ?

Thanks
Wow, old thread, but I get back to things in my own sweet time
Dupla promoted things ands folks seems to follow them much like ADA loyalist today. At least Amano can scape and take better pictures. But the causes, info being given in technical aspects is even weaker. But that's not Amano's goal, he's there to sell products and make $, same with Dupla. My goal is different.
I do not point out that you personally are ever wrong, the idea might very well be however. I do not think in such personal attack mode terms I'd have to be a mean old buzzard if so

So let's see what we can answer for your questions:

What is holding back the algae ?
Let's ask "what is preventing the algae spores from germinating, much like seeds? Algae cells do not live that long, they need to produce new vegetative growth and if no adults are growing, new germinating spores.

So what causes germination is the real question there.
Is any old time good?
Probably not.
Why are they many thousands of algae species?
Algae have adapted to grow when things are most favorable for them, often in a small short window. They, unlike plants, generally reproduce sexually in aquariums.

You try and tinker to see what causes algae to bloom, and you do so with a fully planted well run tank(a control tank).So you add lots of light, high CO2, high non limiting nutrients for both plants and algae, then manipulate the single variable of interest, say NH4. Adding say 1.0ppm of NH4 = GW water.
So next you try this same idea out but this time using progressively overloading the aquarium with fish or shrimp etc all at once. GW.
Now you go back and see if you can induce GW using NO3, PO4 etc.
Nope, cannot do it.

So now you are left with one possible cause(there might be others, but you know what it is not at least for a few things, so you can spend your time testing other fact

Could it be the strong growthing plants releasing defensive chemical against algae ?

Nope, Allelopathy was popular when Diana Walstad suggested it and folks still carry on about it. It's very simple for a hobbyists to disprove the idea that this plays any sort of role in aquariums, as well as never been shown in any natural system to play any significant role:

Add activated carbon to the aquarium/do large frequent, daily water changes etc. This removes those chemicals which are larger organic chemicals which carbon actively binds and removes.

We see no relationship between Ac use and algae appearances, quite the opposite in many cases. Thus this cannot possibly be the cause. for all the talk and implied baloney, this one is easy to test with rather elegant simplicity.

I think Diana could have tested this herself in less time it took to write that chapter There's a long list of why and from myself as well as Ole on my web site about this topic. Folks rarely test things when it comes to algae.
Most are just happy they do not have it and they are not about to test anything. Others are good at rattling on and on, but not doing a thing to test or answer the question, more a peeing match, shouting name calling whine fest

I think if they spend that much passion, ego and energy, the least they could is test a few things and learn. But I've never meet one yet that has done that.........hope blooms eternal

Or highly oxygenated water deter alage to set foot ?

I did this back in 2003, but found the same algae density for several O2 and CO2 combinations. Would have been nice, then we could add O2 gas and kill all the algae

But what signals do you think might be good telling you that the plants are not there and it's a good time grow for a few weeks?

NH4, changes in the CO2, more light suddenly, dead bacteria, sudden influxes of these will.

The other issue is that some appear when the nutrients get too low for the plants, and our lack of care also is a huge factor, so there are social issues as well involved here.

As light, CO2 and nutrients all play roles, the change of any one that tosses the others out of balance for a time period, say 1 week, is enough to cause algae to appear depending on what went wrong and how long etc.

I've been reluctant to say specifics about algae in general. More, better to focus on good plant care.

Why?
Some things may be multifactorial.
I can figure out single variable causes in some cases, but under high light, high CO2 and suddenly adding NH4, will induce GW, but not in other systems. Removing the bacteria from a large filter on an established tank might/may do it as well. But if I have a small fish load, lower light, good CO2, then it might not induce algae.

So there might be more reasons why, more complex than we might assume initially. I answer one question, then I want to know how light and CO2 also impact NH4, and bacteria etc as it relates to algae spore germination.

There's a lot we are just clueless on.