Phosphate Levels And Algae.

[Dave Spencer]

I ask because I am aiming for 2ppm in my tank, but seem to keep overdosing with the stuff. My tapwater contains 1ppm, so I don`t dose a great deal, but my readings always seem to be above target. I suspect the main reason I got algae in my tank is because my CO2 was not high enough from the beginning, but I am wondering whether high phosphates could have contributed too? Thankfully, the algae situation never got out of hand, but it is like having a brand new car. All you see is that tiny scratch in the paintwork that nobody else will ever notice. I have seen quite a nice and varied number of types of algae, though.

I used the Tom Barr calculator to work out my dosage levels, but I suspect I may have got it wrong. This means I will have to mix up a new batch.

Cheers, Dave.

 

[RadaR]

Too high phosphate levels will contribute to algae.

 

[The-Wolf]

yes phosphate levels will directly effect algae growth, as it will some other plant life.

you maybe interested in reading this
http/www.cam.org/~tomlins/algae.html

 

[Dave Spencer]

Thanks for the advice and links, chaps. Think i will dilute my batch of phosphate down tonight.

 

[Underwurlde]

Tell us the calculations you made and the results you got so we can check them for you?

I prepare liquid ferts (using dry) so that adding 1ml of (whatever) increases dosing in my tank by 1ppm. This makes things easy. Others prefer to add dry chemicals directly using small measuring spoons.


Andy

 

[George Farmer]

Contrary to most of what you will hear, I find that in a heavily planted tank with good growth, then high PO4 does not induce algae. My tap has over 5ppm PO4 and I have been changing up to 75% water per day in my nano. No algae.

I have found I can induce algae by limiting PO4.

Of course, this is only appropiate with a heavily planted tank with ideal growing conditions. From experience, I also consider water changes essential in helping to prevent algae where "high" NP are concerned.

 

[Dave Spencer]

Tell us the calculations you made and the results you got so we can check them for you?

I prepare liquid ferts (using dry) so that adding 1ml of (whatever) increases dosing in my tank by 1ppm. This makes things easy. Others prefer to add dry chemicals directly using small measuring spoons.


Andy


I mixed a solution with RO to give 1ppm/ml, but I reckon I put too much fertiliser in.

After what George has said I am pretty certain I erred on the side of caution with my CO2, but I have upped the BPS now and the algae growth appears to be reducing.

 

[plantbrain]

There have been many misapplied approaches and text suggesting high PO4 = algae.
This is true in absense of macrophytes/plants.
The problem is that such advice is based on ecosystems and tanks without plants/macrophytes.

If you add more fertilizer to a lake with say 50% or more plant coverage, you will get more weeds, not algae.

Our tanks are even more obvious.
Adding PO4 to a CO2 or a non CO2 enriched tank that's otherwise in decent growing shape, will not induce algae by itself.

Now if you have barely enough CO2, and the tank is PO344 limited, then the added PO4 willd rive more CO2 uptake, then you can get algae.

But simply because you added more PO4, does not imply that it is a direct relationship. If you isolate the PO4 by having the other parameters, like CO2, in good shape, you no longer tsee that relationship.

Many aquarist confuse correlation with causation and few have tried to rule out the other possible and very plausible factors like poor CO2, low K+, etc.

You also need to start with a decent system of plants to begin with, not an algae infested tank!!
You have issues and have no control to start with.

Then you add PO4 to a stable well planted tank and note the effects while maintaining good NO3, Traces, CO2 etc.

If you do the test fairly, then you will not see high levels of PO4 in a planted tank => algae.
Non CO2 tanks also show this relationship, but they too need to be well planted, decent stable systems. Stable CO2 makes a huge difference and plants do not use much CO2 if they are limited by PO4, they also do not grow nor photosynthesize as much either.

That's fine if that is your goal, but applying a CO2 method for a Non CO2 plant tank method is a bad idea.

Regards,

Tom Barr

 

[Underwurlde]

Tom, have you ever considered writing a book on the subject of EI?

I'd buy it!

Andy

 

[Dave Spencer]

Thanks for that, Tom.

My concern was that as my set up is new, only running EI for a month, I had not yet completely won the battle over algae, and that anything in excess could be used up by the algae. Plus, I have recently carried out a lot of pruning, as my fast growers were bent over at the water`s surface, blocking out the light. A fair amount of the biomass had to be removed and given away, but I didn`t want to create some kind of window of oportunity for the algae.

Nevertheless, there are still a lot of weeds in there reaching for the surface, and the algae remains a nuisance rather than a problem.