Confused About the Conventional Wisdom

Frank Lawler

Member
Apr 15, 2009
60
0
6
Hello All,
Please allow me to explain. During my 5 yrs. in the hobby, more often than not I have experienced algae problems of a greater or lesser degree, more often the former than the latter. Most recently I have been battling a months long case of GDA, which can be quite frustrating, as some of you know. Several times I have tried a 4 day blackout, preceeded and followed by massive water changes. Each time results have been the same: pristine water and glass for a day, followed by a compete green mess several days later. That is, until recently.
Knowing that something had to change, I decided to stop dosing K, and cut in half my previous dosing of traces, P, and N. Previous values for Fe (as a measure of traces), P, and N had been 1.0, 3.0, and 30-40 respectively. Values now are 0.2, 0.5, and 8; lights and pressurized C02 remainin unchanged. Drop checker has always been green, and ph usually drops 0.5 during photoperiod.
The difference has been dramatic. After one week there is still not a trace of algae on the glass, and the water could not be any clearer! The tank has never looked so clean. Plants are not growing as vigourously as before, but they are still growing, and do look healthy. This brings up my main question.
Having been an active follower of this forum and Aquaria Central, I have always followed the maxim that abundant dosing and adequate C02 would minimize algae through the mechanism of healthy plants that would outcompete algae for nutrients. I had the faith, but could not quite understand how a nutrient level above and beyond what the plants were using could somehow mean that less was left over for potential algae growth. Although my recent experience goes against the grain, I am not prepared to discount the knowledge of those with years and in some instances decades of experience with aquarium plants, some of it professional, as with Mr. Barr. Therefore, I am convinced that I must be missing or completely misunderstanding something. Would very much appreciate whatever instruction the advanced members might care to offer. Thanks.
 

dutchy

Plant Guru Team
Lifetime Member
Jul 6, 2009
2,280
5
36
63
The Netherlands
Your conclusion might still be based on correlation. Is it really the nutrient level, or are you now limiting plant growth by adding less nutrients, inducing lower CO2 demand, and the added CO2 is now finally sufficient?

Are you sure your conclusion is the right one? ;)

Plants can never outcompete algae. If a mouse is eating from the same food as the elephant, are they competing? Competition can oly be present if the amount of food is limited. Even so, algae can still draw nutrients from the water at a level that plants can't.

My theory is that algae germinates because of chemical signaling. As soon as a nutrient falls below a certain level, the signal is provided and the algae germinates. When it has germinated, it can maintain itself well into the range where plants grow, but only for some time if all nutrients are higher than the germinating level. Eventually it dies.

With GDA the problem is that the in the zoospore stage the algae is more like a bacteria. It will die with antibiotics. The next thing is that the algae has a lifecycle. As long as we are not able to break the lifecycle, the algae will come back. So the zoospore will die from the antibiotics, while the vegetative state is unaffected. These will make zoospores later. Maybe prolonged use of antibiotics could do it.

Unfortunately I can't tell you what cures GDA. I've tried about everything, including limiting nutrients. What I can tell you is that good CO2 makes a difference.
But this can also be said for less light, more flow and UV.
 
Last edited by a moderator:

Biollante

Lifetime Charter Member
Lifetime Member
Jun 21, 2009
3,210
3
36
Surprise, AZ
Non-limiting Beats Limiting Every Time

Hi Frank,

I am with Dutchy.
:gw

I think what you have done is in many respects like a black out and as many know I oppose shortcuts in general.
:)

After one week, the plants cannot possibly have fully adjusted nor can the nutrient levels changed so drastically.

My guess is that 2-weeks to a month of this regimen will return systemic problems.
:rolleyes:

Then the simple-truth is there are so many variables it is difficult to spot the one that makes the difference.

The thing I am certain of is that in the long-term setting limiting conditions is not the answer.
:cool:

Biollante
 

Frank Lawler

Member
Apr 15, 2009
60
0
6
Hi Dutchy,
I believe that I understand you, but isn't the idea of chemical signaling close to the theory of allelopathy? That theory has always made a lot of sense to me, but unless I am mistaken, Mr. Barr is not an adherent.
Concerning C02, my mineral oil bubble counter shows roughly 5 bubbles/sec (an estimate, since bubble speed exceeds my rate of perception), but since I have always considered this to be sufficient and have always had algae, perhaps my assumptions is more than a correlation.
Biollante,
I hope you are wrong, but suspect that you are right.
 

Tom Barr

Founder
Staff member
Administrator
Jan 23, 2005
18,699
786
113
Frank Lawler;84427 said:
Knowing that something had to change, I decided to stop dosing K, and cut in half my previous dosing of traces, P, and N. Previous values for Fe (as a measure of traces), P, and N had been 1.0, 3.0, and 30-40 respectively. Values now are 0.2, 0.5, and 8; lights and pressurized C02 remainin unchanged. Drop checker has always been green, and ph usually drops 0.5 during photoperiod.
The difference has been dramatic. After one week there is still not a trace of algae on the glass, and the water could not be any clearer! The tank has never looked so clean. Plants are not growing as vigourously as before,

Growing, but not as much as before....this is a key observation.............
You are hardly dosing any P...........So you went from 1 limitation.........to another..............
You had problems prior, but you never corrected them.

So instead of doing that, you limited P. For some who are frustrated, this might seem like causation, but it is not.
PMDD has been around for almost 2 decades as method to limit algae via limiting P.

It is hardly new.

What has been shown many many times since PMDD is that the hypothesis cannot be correct.
That we "limit algae via nutrients." We do not and you said it yourself, the plant growth is reduced and less..........

You just limited P more than CO2.
Prior, you were limiting CO2, not P.

Low to moderately low CO2 is a recipe for algae and plant issues.

Many in the limiting nutrient crowd seem to think this shows causation, they are very incorrect, they do not mention the CO2 relationship nor Liebig's Law of limitation.
It is very easy to falsify this claim, but does little good to the person who never seems to be able to fix things.

CO2 mastery is not easy and most of the top scapers get it and do it well................then there are the chronic folks who never seem to figure this out.
Amano spent 10 years, I spent about 3 figuring out it was all about the CO2.

All I need to do is show a long term tank with high P, N whatever nutrients and no algae and nice excellent plant growth.
It cannot be due to nutrients.

This does not say why anyone else has algae issues that also has high nutrients. It just states what is cannot possibly be, independent of other issues, like CO2, poor care, poor trimming, low biomass, too many fish, and 1001 other possible reasons that are independent of the dosing of higher ppm's.

Such distinctions are lost in the fever of belief and wanting to believe something rather than looking at the test logically.
You also end up NOT learning as much about CO2 as you should, nor can help other folks doing a wide range of dosing routines.
You are stuck back in the mid 1990's with PMDD.

http://www.thekrib.com/Plants/Fertilizer/sears-conlin.html

This was the CW back then.

I beat the crap out the hypothesis because I knew it was incorrect, but I was cautious about it.
It is not that folks have learned something "new", it's that they have had trouble learning good CO2/light management and ended up going back to PMDD as crutch.
This has nothing to do with belief or faith, it has to do with horticulture and controlling light, CO2 and nutrients, you might be able to control nutrients, but learn little about light and CO2.

This is unfortunate.
This result you had in no way discounts the results with aquariums that have high nutrients levels, it only exposed were the weaknesses are with your past approach.
We know all methods do in fact work...........and most work well.

Those are the observations.
I can do any method and have.
I did PMDD for a few years.
I knew and know what that looks like.
I know what sediments can/cannot do over time also.
Non CO2.......very little algae issues there for me, the best in fact. But slow growth, but the plants still do grow..........
And rich sediments/water column ferts and no algae...........

Liebig's law predicts the root issue you had, CO2 I'd say.

The drop checker only drops 0.5pH units?

You need it drop at least 1 full unit to hit the 30ppm range.
Drop checkers are also a poor method to measure CO2 or ensure you have enough CO2, since they only poorly target 30ppm..........unless you use a different KH reference.........etc or indicator solution.

Also, some tanks might need more/less CO2 than others.......this is where the good aquascapers can just look and tell they need to add a little bit more.
Large frequent water changes are also a habit of the better scapers. It's not to remove nutrients, rather, to keep O2/CO2 up and the organic matter down and the tank nice and clean, algae spores out etc.

GDA is a bugger for many to get rid of.............I've only had it a few times and it never lasted that long.
I've inoculated my tanks a few times in effort to get it to bloom. One idea is to go back to the higher ferts, but focus on good CO2 and slow progressive adjustments, these are done once every 2-4 days and then careful watching of the fish/algae and plant growth.

Or if things are easily manageable, you might just stick with what you are doing and there might be little desire to learn more since the result is fine with you.
Both are valid reasons. When someone tries to claim one is better than the other.........well.........this is where social issues more than Science gets in the way.
 

Frank Lawler

Member
Apr 15, 2009
60
0
6
Mr. Barr,
I very much appreciate the extended reply. For some reason my C02 indicactors seem visually profuse, judging by bubble counter, drop checker, and diffuser output, to the point where I am misled concerning C02 adequacy. Perhaps there is an outgassing problem, even though my HOB filter output does not cause splashing?
My next step, then, should be to cautiously increase C02 while carefully observing fish behaviour, then back it off just shy of the point at which their behaviour changes. If plant growth increases and algae remains absent, I would then attempt further gradual increases of both C02 AND nutrients.
 

Gerryd

Plant Guru Team
Lifetime Member
Sep 23, 2007
5,623
22
38
South Florida
Frank Lawler;84442 said:
Mr. Barr,
I very much appreciate the extended reply. For some reason my C02 indicactors seem visually profuse, judging by bubble counter, drop checker, and diffuser output, to the point where I am misled concerning C02 adequacy. Perhaps there is an outgassing problem, even though my HOB filter output does not cause splashing?
My next step, then, should be to cautiously increase C02 while carefully observing fish behaviour, then back it off just shy of the point at which their behaviour changes. If plant growth increases and algae remains absent, I would then attempt further gradual increases of both C02 AND nutrients.

Hi,

I am not Tom of course (to my dismay) but the plants and fish are the best indicators of c02 balance. That and the non existence of algal issues.

That said, you are spot on with the rest of your reply.
 

Frank Lawler

Member
Apr 15, 2009
60
0
6
I suspect that I may be misjudging the outgassing effect of my HOB filter. Next time I am home all day I shall unplug it and see what happens. If there are unmistakeable signs of a C02 buildup, perhaps the next step would be to put it on a timer.
 

Tom Barr

Founder
Staff member
Administrator
Jan 23, 2005
18,699
786
113
Frank Lawler;84442 said:
Mr. Barr,
I very much appreciate the extended reply. For some reason my C02 indicactors seem visually profuse, judging by bubble counter, drop checker, and diffuser output, to the point where I am misled concerning C02 adequacy. Perhaps there is an outgassing problem, even though my HOB filter output does not cause splashing?
My next step, then, should be to cautiously increase C02 while carefully observing fish behaviour, then back it off just shy of the point at which their behaviour changes. If plant growth increases and algae remains absent, I would then attempt further gradual increases of both C02 AND nutrients.

CO2 is a bugger.

I kid no one about this fact.

It seems to me, those that have good observation skills regarding plants and livestock tend to be the best aquarist and care for these things more/better than the most techy Scientist egg head.

Every tank will have a CO2 sweet spot and it is different for every tank, so a ppm might not be the best solution.
I've had tanks where 15-20ppm worked well, but others needed 70 ppm to do the job.

Drop checkers really have been around since 1985 or thereabouts, Dupla use to set them.
I think the pH meter is a better RELATIVE device.

You use the pH/KH to get close, then slowly reduce the pH every 3-4 days and watch carefully. Say 0.05 pH units or thereabouts, maybe 0.1pH units.
Some folks have done this with a pH controller.

Whatever works.

The above is a much tighter measure of the CO2 differences between treatments than any color test kit like the drop checker.
If you could withdraw the color from the drop checker and place ina colorimeter/spectorphotometer, then you could get pretty close, or better yet, use the pH probe in the reference KH solution inside a drop checker, then you are getting close.
Or, add a 4 degree KH ref solution in a thim membrane wrap around a flat tips pH probe and you can CO2 meter with fairly responsive/fast readings(under a min if the volume of the KH solution is say 200 ul)
Another way is to do massive water changes with RO and add a little baking soda to make the KH about 1 degree, then use the pH/KH chart.

There's a few ways to do all this, few bother and it's just plain easier for most to eyeball the plants/livestock carefully, since that is the goal and the interest of the hobbyists typically.
Not test kits and methods and all that jazz.

I have a post observational interest in it..........but only after I have a nice well run tank to test.
If all you have is a tank with lack luster growth or algae etc, then this is a poor tank to test, since there's little control and results we want.

I'd personally get rid of the HOB filter.
Canister or Wet/dry.

Pics of the tank.

If you look on line and on the various forums, you will read about 1x a week, someone gassing and killing their fish with CO2 or overdosing Excel to kill algae etc.
But folks blame nutrients.

The best article on light and CO2 is from Tropica, it's a VERY good read.

Look at figure 1 and then at Table 1. Table has every range of both light and CO2 that the typical hobbyists might have or use.
You can see, for each and every case, there is positive growth rates. Nutrients are non limiting thereby independent of light/CO2.

Now you can do a similar test by making CO2 and nutrients non limiting and then measure light only, or make light and CO2 non limiting and then change nutrients, the Barrel model from Liebig still applies.

http://www.tropica.com/en/tropica-abc/basic-knowledge/co2-and-light.aspx

Read this a few times, make sure you fully understand it.
 

Gerryd

Plant Guru Team
Lifetime Member
Sep 23, 2007
5,623
22
38
South Florida
Frank Lawler;84446 said:
I suspect that I may be misjudging the outgassing effect of my HOB filter. Next time I am home all day I shall unplug it and see what happens. If there are unmistakeable signs of a C02 buildup, perhaps the next step would be to put it on a timer.

Yes, I like to turn the c02 OFF in the middle of it. Observe for 20-30 minutes and see if the fish behave any differently. I have caught myself a few times providing more than I felt comfortable with via fish behaviour.

Slow and easy does it with c02. It is a killer, more than any nutrient overdose....
 

Tom Barr

Founder
Staff member
Administrator
Jan 23, 2005
18,699
786
113
Frank Lawler;84446 said:
I suspect that I may be misjudging the outgassing effect of my HOB filter. Next time I am home all day I shall unplug it and see what happens. If there are unmistakeable signs of a C02 buildup, perhaps the next step would be to put it on a timer.

The CO2 is run 24/7? Is it DIY yeast or a gas tank?

Some more details about your set up, pics etc, are helpful.
You can always come back to PMDD type dosing etc if anything goes awry.

This is where these nutrient limiting methods help in the meantime till you figure out the other issues.
 

Frank Lawler

Member
Apr 15, 2009
60
0
6
It is pressurized C02, starting an hour before the lights come on, and going off an hour before they do. I have a 55 watt AH Supply Kit set 4" above the tank, which is 29 gals. and contains 22 tetras of various kinds. The pencilfish occasionally produce babies, which may suggest good water quality. I gravel vacuum and do a 30% water change weekly. Regarding dosing, I add N,P,K, and trace powders in my own pre-mixed solutions of distilled water. Unfortunately this leaves me unable to determine the exact amounts of each that I add to the tank. In two days I will be able to post pictures.
Thanks again for still more information and advice. I read the Tropica article carefully; it is well written and I think I understood it.
Now its time to have a look at filter alternatives. And yes, I will be very careful with my C02 adjustments.






ah
 

Biollante

Lifetime Charter Member
Lifetime Member
Jun 21, 2009
3,210
3
36
Surprise, AZ
How Do You Know Limiting Or Non-limiting If You Do Not Know What Is Going In?

Hi,

Tell us what you are adding to your fertz concoction, be as accurate as you can, but it does not have to be exact and some smart person will calculate it for you.
:)

And if we cannot get a smart person I will
:) and Tug will make sure I get it right.:rolleyes::eek:

It is hard to be limiting if we do not know what we are limiting.
:gw

Also even though The Military-Industrial-CO[SUB]2[/SUB] Complex doesn’t like it I have found that in addition to CO[SUB]2[/SUB], high dissolved organic material can be a cause of chronic algae.

Biollante
 

Frank Lawler

Member
Apr 15, 2009
60
0
6
In 500 ml I have: CSM+B -1/2 cup Add to tank: 4 ml every other day
P-4 tsp " " : 4 ml " " "
K-7 tsp " " : 4 ml " " "
N-15 tsp " " :10 ml " " " .
Hope this is not too confusing. As mentioned, this was my previous routine.
 

Biollante

Lifetime Charter Member
Lifetime Member
Jun 21, 2009
3,210
3
36
Surprise, AZ
How Much Do Dentists Get For Pulling Teeth?

Hi Frank,

Can you tell us what the “P,” “K,” and “N” are?
:confused:

When you mix this concoction, do you start with 500-ml of (water? distilled?) or end up with 500-ml of stock solution?

Possibly we are on to something...
:)

Biollante
 

Biollante

Lifetime Charter Member
Lifetime Member
Jun 21, 2009
3,210
3
36
Surprise, AZ
I Think I Know What Happened, Is Happening, Please Bear With A Little More Dentistry

Hi Frank,

Would be kind enough to tell us the volume of your aquarium?
:)

In your original post you rattle off some numbers for Fe, P and N, are these calculated or measured values?
:confused:
  • If measured how long after dosing?
    • After dosing how much?
  • Are (were) the test kits calibrated?
  • Are (were) you measuring elemental P and N?
    • Can you tell the method or test procedure?

Are there bits of stuff at the bottom of your stock solution container?
:eek:

What is the container and how is it stored?
:)

Biollante
 

Frank Lawler

Member
Apr 15, 2009
60
0
6
Hi,
I meant P for KP04, K for KS04, and N for KN03. I end up with 500 ml solutions AFTER adding the ferts, and no, there is no residual powder at the bottom of the bottles, which are old ADA bottles and stored in a drawer at room temperature. The values given earlier were measured roughly 24 hrs after dosing the amounts listed in Post #14. I use non-calibrated API test kits which measure N03 and P04, and a Nutrafin kit which measures chelated iron. Tank size is 29 gals.
 

Frank Lawler

Member
Apr 15, 2009
60
0
6
Tug;84486 said:
The light? Is it one 55 watt AH PC and how far above the substrate?
It is one only T4 high output florescent bulb, 20" above the substrate. At a time when the tank seemed to be mostly free of algae I lowered it by 2", only to cause another algae outbreak.