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Po4 levels

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Gang@Ukaps

Could somebody explain the consequences of high Po4 levels greater than 3.0 mg/l within the water column.

Regards
Paul.
 

Dolly Sprint 16v

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George

What the difference between ppm and mg/l.

I measured mine 2 weeks ago and the reading was 5.0mg/l and you hear rumors that a high level of Po4 assist the algae spores to grow - any truth in this statement.

Regards
paul.
 

George Farmer

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Hi Paul

There is no difference in ppm and mg/l.

High PO4 is said to trigger algae in poorly planted tank with poor biomass, filtration, CO2 etc. but I'm not sure if it's the high PO4 that really causes the algae.

In non-planted tanks minimising PO4 can limit algae.

If you have a well set-up and maintained planted tank, then high PO4 won't cause issues. Too low PO4 is more an issue, as is low NO3. It's better to have more NO3 than PO4 but the exact ratio doesn't seem important IME.

Flyfisherman said:
George

What the difference between ppm and mg/l.

I measured mine 2 weeks ago and the reading was 5.0mg/l and you hear rumors that a high level of Po4 assist the algae spores to grow - any truth in this statement.

Regards
paul.
 

Dolly Sprint 16v

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George Farmer said:
Hi Paul

There is no difference in ppm and mg/l.

High PO4 is said to trigger algae in poorly planted tank with poor biomass, filtration, CO2 etc. but I'm not sure if it's the high PO4 that really causes the algae.

In non-planted tanks minimising PO4 can limit algae.

If you have a well set-up and maintained planted tank, then high PO4 won't cause issues. Too low PO4 is more an issue, as is low NO3. It's better to have more NO3 than PO4 but the exact ratio doesn't seem important IME.

Flyfisherman said:
George

What the difference between ppm and mg/l.

I measured mine 2 weeks ago and the reading was 5.0mg/l and you hear rumors that a high level of Po4 assist the algae spores to grow - any truth in this statement.

Regards
paul.

Thx for the reply - i would imagine that you must have read my thread regarding "Packing in and my return" I posted two pic regarding my tank within the tread - how it was prior to Christmas and how it is now Inc the reasons for the change. Would you say the my tank is poorly planted which would produce a poor biomass.

Regards
Paul
 

GreenNeedle

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High PO4 is what environmental 'specialist' always blame green water in ditches, rivers, lakes etc on.

They also blame every other nutrient that drains in from agricultural fertilisers that inevitably end up in watercourses.

However as Tom Barr rightly states they don't take into account the fact that they rip all the 'weeds' out of these water courses regularly and never let anything grow properly. Therefore low plant biomass causes the algae. Then the algae FEEDS off the nutrient as there are not enough plants competing with it.

That is why they get paid so much by the government to provide answers to problems without taking into account all possibilities ;)

In answer to your question If you have high PO4 and are growing a good biomass (not necessarily as large as many of mine) then nutrient (including PO4) should not be an algae causitive unless something else like CO2, light, flow are not adequate for each other.

If you were to dredge loads of the plants out (or in our case pull them out) then you would almost certainly see algae immediately.

Next time you look at a waterway check out how little plants they leave in it and then check out the clarity. Then compare it to an untouched woodland stream ;)

AC
 

JohnC

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Hi,

My tap water varies from 5ppm to 9ppm over a year and now I've nailed all the other dosing issues in my tank i have zero algae.

When I got the report from the water board for the last year I vaguely remember the guy telling me they add phosphates to tap water to prevent lead poisoning in areas with old pipes. Hence the high values in Edinburgh. I am going to check my water board again in the next few months for the levels as they have been replacing all the local pipes with the stupid tram works. If they drop the phosphate levels in the local leith water I might end up in trouble as i don't add any with my EI dosing.

Best Regards,
John
 

JohnC

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Flyfisherman said:
Thx for the reply John, do you have any algae within your tank ?.


Regards
Paul.

Any algae issues i've had over the years have been caused by other things like low nitrates, low traces, fluctuating or low CO2, bad circulation. High phosphates in the water as mentioned above is just free ferts for a planted tank.

Best Regards,

John
 

mzm

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hi I am currently battling a bba algae problem. I removed gravel which had bba on it last Saturday and today, only 4 days later, spots of the stuff are visible again. I bought a phosphate test kit and it indicated a reading of 10mg/l. I have plants but wouldnt say its heavily planted. I dose EI which means I am adding potassium phosphate every other day. do you think that removing / lowering the phosphate will help eliviate my bba problem? I have tried all the other things like adding more co2 input, increasing flow and reducing light to only 6hrs per day and that didnt seem to stop it.

Michael
 

mzm

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By the way I have eliminated the ph controller and have set it to a timer in order to make sure that ph levels are constant. its on 3hrs prior to lights on and off 1hr prior to lights off.
 

ceg4048

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Hi,
BBA is not related to PO4, it is strictly a CO2 related algae. One can however mitigate the growth rate of the CO2 related algae by lowering the nutrient load. It seems to me folks still have not grasped some of the fundamental concepts. In our tanks, poor plant health triggers algal blooms. The type of bloom triggered is a function of (or at least is closely related to) the type of health problem. Therefore nutrients don't trigger algae. Health problems trigger algae.

Algae start life as spores. These spores are sitting around, sampling the environment and waiting for specific conditions to occur. When the required change occurs in the environment they bloom. Think about fungus for example. We are all familiar with fungal spores. But those spores will rarely bloom into fungus while in a dry desert for example. The conditions just aren't right. If you move those spores to a moist shaded forest, perhaps at a certain temperature and humidity they will bloom.

Algal spores roughly follow a similar life cycle pattern. These spores are always in your tank, waiting for their particular favourite conditions. The conditions favourable for most of our algal species include some conditions NOT favourable to plants. So if a plant is denied a specific nutrient, then that failure, in combination with light, will trigger that type of spore to bloom.

In the case of BBA unstable delivery or uptake of CO2 causes a specific set of reactive failures in plant tissues. BBA spores read the failure, read the conditions and then bloom. Once the spores bloom into the flagellate form we see (and in this case describe as a black brush) they will then feed on whatever nutrients are available in the water - but it was not the presence of those nutrients that trigger the spores to bloom. Once the algae blooms, this form likes the same things that higher plants like. They like CO2 and they like nutrients and they certainly like light. This is what makes algae so tenacious. BBA is particularly tenacious because the flagellate form loves CO2 - so just because you fixed the CO2 it does not mean automatically that it will go away. Unstable CO2 is comparable to Pandora's Box. You have to do two things:
1. Fix the conditions that triggered the spores to bloom, i.e. stable, adequate levels of CO2
2. Remove every trace of the flagellate form (remove every affected leaf) and do frequent and massive water changes to remove spores.
3. Lower the light, at least for a while.

This might require a few weeks of elbow grease because the plants are still unhealthy. Just because you fixed the CO2 yesterday it doesn't means that today the plants have been cleared to leave the hospital. They need to recuperate. During these few weeks BBA continues to grow. Excel OD can be used to kill the brush, or it can be applied directly to the sites during a water change via spray bottle or syringe.

So the only way to coexist with algae is to prevent the spores from blooming by keeping the plants as healthy as possible, and that means providing a set of environmental parameters that are plant friendly - adequate levels of nutrition and adequate levels of stable CO2. Excessive lighting, poor nutrition and poor CO2 immediately breaks this system and triggers the bloom.

So in this particular case, because of this particular species, one can certainly lower the nutrient load, including PO4, to help reduce the acceleration of the BBA, but be aware that lowering PO4 should never be considered a unilateral response to all algae because there are some forms of algae that bloom and accelerate when plants are starved of PO4. So if you convince yourself that PO4 and other nutrients are the root of all evil, you're going to be battling poor plant health and algal blooms for a long time because plants require 1000X more PO4/NO3/K than algae do.

Cheers,
 

mzm

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thanks for your input.

I now should have stable co2 since i eliminated the controller and have a steady flow which comes on 3 hrs before lights on and goes off 1 hr before lights out. I have had this running this way for two weeks now. There obviously are fluctuations in co2 between the time it goes off and the time it goes on again. I have two Eheim drop checkers one at each end of the tank and both are lime / yellow (one of my discus is not too happy about the amount of co2 being pumped in).

Flow seems to be ok since drop checkers indicate good co2 levels all over.

Lights are only on for 6 hrs a day. Should I reduce this? I have a 350l corner tank with 2 x 48W tubes and 2 x 28W Juwel T5's.

I dose EI and according to your recommendations i should continue to do so.

I do about 30% water changes every Saturday.

Michael
 

ceg4048

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Hi Michael,
Fluctuations only really matter when lights are on, not when they are off. So when you turn everything off the CO2 levels will slowly decline overnight. Then, by turning on the gas while it is still dark, you are allowing the CO2 level to rise and stabilizes, so that by lights on the level is adequate. If the Discus is uncomfortable then definitely make a small adjustment downwards so that the injection rate is slightly lowered. Remember that in this case the BBA is triggered by instability as opposed to low levels of CO2 so we just need to fix the fluctuations right now and keeps it stable during that 6 hours.

I know it's frustrating but we just need patience now. CO2 injection is THE single most difficult technique in all of plantdom. T. Barr estimates that well over 90% of all planted tank problems are due directly to poor application of CO2. That you are attempting this with valuable fish in the tank doubles your degree of difficulty, so one really needs to sit back, take a deep breath and not lose faith.

Flow and distribution is always an issue with oddly shaped tanks. When you look at the plant leaves are all or most of them gently "rocking in the breeze" so to speak? This is how one determines whether flow/distribution is good, not just from the flowrate numbers.

150 or so watts over a 90 USG for 6 hours is OK. When things are sorted you should easily be able to run this for 8+ hours.

Have you considered short term use of Excel/EasyCarbo? These products have taken a reputation hit recently, but there is no doubting that they really do a good job of kicking BBA in the groin mate. You can do a 2X-3X overdose and start to see BBA die-back within days.

Ideally, when you have BBA and are trying to treat it, a 2X-3X per week 50% or more water change is the way to go. Your work schedule may not allow that but it is the ideal...

Cheers,
 

mzm

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Hi,

All plants seem to be swaying somewhat and I also added an additional drop checker at the other end of the tank and both indicate same lime colour.

I wouldnt mind treating with Excel however my Valisneria would definitely pack it in if i were to do so so i am a bit skeptic about that although i am really tempted!!
I suppose from now on its a waiting game.

Regards,
Michael
 

dw1305

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Hi all,
High PO4 is what environmental 'specialist' always blame green water in ditches, rivers, lakes etc on.
&
If you were to dredge loads of the plants out (or in our case pull them out) then you would almost certainly see algae immediately.
This is 100% correct, have a look here <http://www.science-aquinas.co.uk/biology/eutrophic.htm>, cultural and agricultural eutrophication, and particularly high PO4 levels are the cause of much of the poor water quality in the UK's ponds and rivers. What you have to remember is that ecology is rarely a black and white issue, but the whole environment in the UK is awash with phosphorus (and nitrogen) at something like X10 of the natural amount and the relationship between phosphorus and algal abundance is easily demonstrable.

Phosphorus is the limiting nutrient in nearly all fresh water systems and come from sewage, optical brightener in detergent and agriculture. Plants do require large amount phosphorus, but about X10 less than either nitrogen (N) or potassium (K), the other difference between them is that N and K are highly mobile and are rapidly leached into water courses, where they remain soluble. Phosphorus does not it, it has a high "anion exchange capacity" and is tightly bound by clay minerals, and forms partially soluble calcium phosphate complexes at alkaline pH's, you than end up in a situation where the sediment forms a reserve of phosphates which repeatedly become available when the sediment is disturbed, leading to a cycle of algal bloom and decay, often followed by oxygen depletion. This is why most UK sewage plants now have phosphate strippers on them, but this is really trying to put "the genie back in the bottle" as the phosphate loading of many fresh water sediments (and clay soils) is huge and will take literally millennia to deplete back to natural levels, even if the addition of phosphorus stopped tomorrow.

As part of our work on landfill leachates we were involved with something called the "trophic diatom index", and I've got a copy of "Use of diatoms to monitor eutrophication in UK rivers" if anyone wants one? It is a good read even if its not your field on interest.

cheers Darrel
 

plantbrain

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The other issue of difference is that aquarist can control light intensity and duration/CO2.

For environmental management, how might you try and change the CO2 or light in a river or stream in the UK?
PO4, NO3, etc are pretty much the ONLY tools you have to work with. the othe rissue is restoring a natural system to the way it was, our systems are artificial for the most part. They have their own type of Ecology and management.

It's easier to change what we have done with nutrients, than try and modify the other things like CO2/light.
We seem to be slowly modifying the CO2 though as well!

In CA, N, not P is the typical limiting nutrients, same for the springs in Florida, N levels have increased 10X in the last 20 years and algae has increased. N or P, it can go either way, but the bottom line is to keep it out of the environment and use better management for agriculture and reduced carbon oxidation, N/P limited methods for larger scale systems, wetlands and weir like water runoff retention basins. Folks do not like to give up their agricultural lands for this type of thing. So there's a fight typically/legal political environmental amongst several groups or more typically.

We are good at this latter part in CA :crazy:
Plenty of agriculture, fisheries, drinking water(too many people) and politics to go around and a very limited amount of water.

We also use the Diatom index for stream monitoring here in CA and the USA, a very typical method for measuring the trophic status and a good one. Aquarist can also use algae as a bioindicator for their ecosystems as well.

BBA: CO2
BGA: low NO3, poor filtration, cleaning etc needed
GSA: more PO4 , maybe low CO2
Hair algae: higher greens: slightly low CO2, too much light
Diatoms are typical only during the intial start up, too tasty to Otto and most other species.
I think Dusko's site gives it a good run done.

I've long used the algae are monitors and can tell what is going in a tank in a few seconds along with the plants if I see it in person. Algae do not lie, various ppm's etc can.

The problem is when we have lots of plants and other autortrophes, we still have high ppm's of nutrients, and weedy aquatic macrophytes, but no algae, then such indexes do not work well. We add more nutrients, we simply get more weeds, not algae.

This is typical for many sites in CA, Texas, Florida, LA, AL, etc.
Warmer lower shallow lakes, stream systems where there's weeds already.
I think wetland creation is the best way to remove and sequester the PO4.
Works well in semi tropical regions, but does little good in the winter in northern Europe.

Regards,
Tom Barr
 

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