Rate of macro and micro nutrients consumption

[FC]

I would like to invite all to participate in this survey concerning <<Rate of macro and micro nutrients consumption>>. I believe the feedback collected would served as a valuable information for those interested to gauge how much to add to their tank.

In order to make the survey more accurate and to minimize feedback typing works, for those within below ranges (that affect nutrients intake rate) need not specify the tank parameters:
1) Lighting between 0.5 to 0.8 watts per litre (of tank water)
2) Lighting period 9 to 10 hrs
3) CO2 between 20 to 30 ppm
4) Light to moderate fish load
5) Temp between 26 to 29 degree Celsius
6) Have addition of and kept at NO3 (3-10 ppm), PO4 (0.2-1.0 ppm), Mg (2-6 ppm), K (15-25 ppm), Ca (10-20 ppm or 1 to 2 GH)
7) Feedback must be based on more than 2 months observation

Those outside the above ranges, kindly specify your tank parameters (ONLY those that differ) in your feedback.

Kindly specify the rate of consumption (IN ppm per week) of the below listed wherever applicable:
1) Micros - based on Fe level/consumption
2) Macros
a) NO3
b) PO4
c) Mg
d) K (estimated)

It would be good to mention how you derive the consumption rate.

Thank you.

[Allen_1971]

FC,

I strongly suspect few people would be able to provide you the detail which you are asking. True, I'm curious myself to know just how much my plants are consuming. However, I have no real idea as to how much my plants are consuming...

[bclee]

There are some complications I foresee, in particular for NO3, PO4, Fe and fertiliser in substrates.

We are consistantly feeding the fishes and these will contribute NO3 & PO4 which cannot be measured.

Some Fe will precipitate rather than being consumed by plants directly from the water. The precipitated Fe may than later be consumed by plants via roots.

Fertiliser in substrates will be both consumed by plants and leech into the water column.

Different plants have different consumption rates.

Taking into consideration of the above, tanks will vary quite significantly from one another. The data collected may not be as useful to another person's tank.

But it will be interesting to find out the differences.

BC

[FC]

Allen,

Thanks for your feedback. I believe there are serveral ways to measure that. 1 simple way is to check after addition in the beginning of the week and check before adding at the end of the week. Adjust the dosage accordingly and after few weeks you be able to gauge the consumption.

+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
Allen and bclee,

I knew this is a difficult survey, I just started it, hopefully to create new topic with weight as things are running dry. I appreciate your concern on the accuracy of the survey, I had thought of it all and more than you mentioned. If you have a better idea on how to start this survey, please add-on to where I had left off. I believe that would be more productive.

The idea is to make it simple and to gather a rough guideline for everyone to tap on. I believe, if the survey were to be well participated, it would shed new lights to the hobby. You would not know where it will lead to....but keep the topic level high, grow up.

I would like to invite both of you to feedback, doesn't matters if you made a mistake or... just relax.

Have fun.

[vinz]

Hmmm... you'll have to give it a few days so that those interested can go do the measurements.

1) Micros... those using Flourish will have a problem here. Fe is a seperate. Unless the user tags the dosage of Flourish to the Consumption/dosage rate of Flourish, assuming the recommended dosage are complimentary.

2) Macros, how to estimate consumption of K, and Mg (GH drop)?

[FC]

Vincent,

Micros:
Seachem recommendation is contradicting; take flourish for example, on one hand it says 1~2 ml per 200L water, 1~2 times a week, on the other hand, it says the bottle last 4~6 mths for 100 gallons water. I had derived the dosage myself for my tank (360L water nett) that fortnightly, I dose a total of 15~20ml flourish and 15ml flourish Fe. That would typically keep my Fe level average at 0.2. That handles all my micros requirements.

Macros:
Estimating consumption of K is a bit tricky. I handle them in a passive way to avoid SO4 overdose. I would dose the other macros to recommended levels mentioned in this topic opening, then I add K to drive their level down to their threshold levels (lower limit of the range) or even to none. After a couple of weeks of trials, I got the dosage right.

Through the above, I also discovered why well known commercial fertilizers are recommending weekly/fortnightly dosage and change water fortnightly. I also realized I had been grossly under dosing in the past.

Having said that, I have a different way of handling all the liquid fertilizers. I inject all, except K in the substrate. The followings are my tank’s parameters highs (3 days after water change) and lows (2 weeks after water change):

1) PO4 0.2~0.6 ppm
2) K 10~25 ppm
3) NO3 2~6ppm
4) Fe 0.1~0.4 ppm
5) Mg 1~4 ppm
6) SO4 15~40 ppm

[kc]

Very Cheem.

Looked like I'm getting into deeper and deeper water.

[FC]

I would like to know whether anyone is interested in the survey?

Thanks.

[vinz]

I am, but it's been a busy week and I'm about to redo 1 tank...

[Plantbrain]

Big issue.

CO2 I'll ignore except to say it's in a good shape and not ever in limiting amounts.20-30ppm

Nitrogen.
Well, you have to forms, NH4 the reduced form and the oxidized NO3 form.
Fish, critter load will supply the NH4 form. Difficult to measure this directly as heathy plants will suck this quickly out of the water much faster than NO3.
Fish load has a good deal to do with this but generally it's limited in most planmt tanks as it should be.

NO3, some have said that NO3 is converted into N2 gas by anaerobic bacteria in the gravel.
Well, I've removed the plants and added KNO3 and NO3 did not dissappear for a week.

So most of it is going into the plants. I can test for the water column and based on the uptake rates, the NO3 has to be moving into to something rapidly.

NO3 uptake rates in my tanks have been around 3-4ppm a day at high light. So 1-4ppm is a decent range to expect.

PO4, about a 10:1 ratio of N:P.

Traces? Forget it.
Way to many issues to even consider an uptake rate.
Iron complexes into many forms and also forms complexes with many organics and also preciptiates out etc. Test kits, even the nicer Lamott/Hach kits are no good for this.

Best way to see what an optimal amount to add is having all the other nutrients in a good range doing, then add this till you no longer see a positive plant respose.
For me that is about 5mls per 75.7 liters 3x a week of TMG or Flourish or Sera. It's is unlikely anyone needs more than this for their plants.

I dose the same amounts of nutrients on all tanks, but if the tanks have less lighting, I change the frequecy of dosing, not the amount for each dose.
less than .5w/L 1x-2x a week might be enough, .5 to .8w/l 2x a week, more than .8w/l 3x a week etc.

Regards,
Tom Barr

[Plantbrain]

Oh, GH should be at or above 3GH/50ppm and hopefully at a 4:1 ratio of Ca to Mg. SO4 is added via K2SO4 in sufficient supply(Excess like all of these).

My Gh was 25 degrees or about 450ppm. Plants grew great. I know only have 5GH/KH 3 which is nice also.

Regards.
Tom Barr

[FC]

Hi Tom,

Wow, very comprehensive information. Thanks alot.

"PO4, about a 10:1 ratio of N:P"
Good confirmation, I experienced the same consumption ratio. My latest dosage has the PO4 & NO3 in that proportion.

"Traces? Forget it."
I am not sure what you mean but I do have problem measuring Fe level with Sera test kit unless I keep the level at or above 0.5 ppm.

"For me that is about 5mls per 75.7 liters 3x a week of TMG or Flourish or Sera."
I am not sure whether TMG, Flourish and Sera are on par when coming to dosage. I suppose that Flourish has a much higher concentration than the other two (especially in Fe). If that's true, Flourish should then be more economical (may be 2 ml per 100L, 3 times a week?). Kindly elaborate.
What do you think of PMDD after all these years? Do you use it?

"GH should be at or above 3GH/50ppm and hopefully at a 4:1 ratio of Ca to Mg."
My water source has 0~1 GH. I add Ca by using coral chips (CaCO3) -is it a good Ca source in your opinion? I like it because it also produce some KH for me. I place them (half handful) in the canister filter for my 4x2x2ft tank.
I do not have Ca/Mg test kit. Since my water source has zero GH, is it right to get the Ca reading by using the GH reading, then subtract the Mg that I add?

Thank you in advance.


Regards,
Freddy

[DEA]

ooh
tom barr is here
*waves at tom*

anyway
i don't mean to pour cold water on anyone
but at best these readings would be considered anecdotal
unless everyone putting the exact same things into their tanks (like what bc mentioned) and everyone has the same kind of plants in the same numbers, the values will be different for everyone

what we CAN do is get a rough range and aggarate from that range what we should be adding to our tanks
not to slight the sears-conlin collaboration, but i feel that micromanagement down to the ppm level is highly unrealistic

good job FC
if you manage to get enough responses to tabulate, send a copy to me?
if possible i'd like to put it into the FAQ

[hoppinghippo]

How do you measure Mg in the tank? there's no test kit at all for Mg rite? I"m quite interested in how Mg features in the tank, are there any commercial ferts which supply Mg alone?

[Plantbrain]

FW algae have 14:1 ratio FYI.

Fe test kits simply do not tell you anything about the plant or the bioavailability of iron in the water column.

I don't recommend them at all. Even Hach Lamott etc.
I've never found good results. Fe complexs into many inorganic forms in water solutions. Then there's the organic complexs. Determining the amount needed is much more a visual determination, not a quantitative one. Fe levels jump all over in the tank depend on when you dose and when you test and how long you let the test resolve for. Even then it's difficult to say with the complexs. They whole books on the topic.

I use the TMG/Flourish and Sera all about the same.
I might be wasting the flourish some but it's doesn't hurt either. One's ETDA and the other is gluconate bound.

No, I never used the standard PMDD.
I use dry KNO3, K2SO4, traces, KH2PO4 etc separate.
Always will.
PMDD is a great idea and a good stepping stone into the real issue: healhty plant growth which is the goal.

With low GH, using the CaCO3 is fine, I'd add some MgSO4 also though. Need some of the SO4 also which is used in fair amounts by plants etc.
I use CaCl2 for Ca and MgSO4 for the Mg.

I'll use baking soda for KH.
But CaCO3 works.

Try fine ground aragonite for CaCO3 source as it will dissolve the best for you.
CaCO3 is real tough to dissolve but that will help some.

[Plantbrain]

Here's the deal with different tanks etc and micromanagement etc.

I came up with a "range" of parameters, not once set point. That would be too inflexible.

50% weekly Water changes+ dosing after wards and a guess at mid week will yield the the ranges easily without much/any testing at all.

I've been doing this for many years and on many tanks.
It's based on what's best for a plant.

It's also based on _max_ growth rates so it's unlikely anyone would need more and run into a deficiency.

Since 50% weekly water changes are done, nothing ever builds up if you have less than max growth/high light etc.

For less light, _the frequency_ is reduced to once a week, but the _the dosage_ stays the same.

So a low light tank uses 1 dose a week, a mid light tank uses 2x a week and a high light will use a 3x a week routine.

I works very well with every set up and water types etc.

Not too much and not too little. No test kits either except pH/KH for CO2.
But it took test kits to figure it out

Regards,
Tom Barr

[FC]

Hi DEA,

"i feel that micromanagement down to the ppm level is highly unrealistic"
I am interested and enjoy finding out during my leisure time what my plants like to have to the finest details possible because they are my hobby’s single most important element.

To truly enjoy plant as a hobby, this direction is inevitable if one wish to improve and go on with the hobby. Why? OK, some fail to see the point that a nice aquascape is nothing without the plants being healthy and algae free. On a different note, healthy plants will presence its’ natural true colours, shape and size on all their parts and these alone speak loud enough without sculpturing them. Aquascape will change but the plants not.

[FC]

Hi Tom,

I hope I am not asking too much but what are your reasons to have such a high light (more than 0.8 watts per litre) for some of your tanks?
I ask because I am pretty happy with my 0.6 watts/litre setup and wish to know what further advantages I could get in increasing the light. I am reluctant to move to high light zone because that would also move me to a more critical zone where any slack in nutrient regime would lead quickly to deficiency.

In my observation, any fully planted tank, regardless of plants used (except super-slow growth plants), that has the tank parameters stated in this topic opening, would have negligible difference in nutrient uptake. The factor that varies their consumption is the light intensity. Do you experience the same?



Thank you,

Freddy

[Plantbrain]

My high light tanks showed the deficicencies faster and more clear when one is present.

This leads to a better understanding and optimization at lower levels where things might not be so clear.

I personally like trimming and growing plants fast.
I also don't mid dosing 3x a week vs 2x a week.

But beyond this, there's not much else.

It's easier for folks to drive a tank at lower lighting for certain.

Unless you keep up on things, the extra light is wasted to causes algae if the plants remove everything then stunt.

I don't recommend over 2-3w/gal or about 0.8w/L.
But many people have lighting like this or higher here in the USA. So you deal with it

Regards,
Tom Barr

[DEA]

----------------
On 2/25/2003 10:28:18 AM

To truly enjoy plant as a hobby, this direction is inevitable if one wish to improve and go on with the hobby. Why? OK, some fail to see the point that a nice aquascape is nothing without the plants being healthy and algae free.
----------------

i see where you're going
however, it is VERY POSSIBLE to get tanks that have no algae PROBLEMS and have healthy plants without even bothering to measure any of the water parameters
why then should it be inevitable?

but the important thing at the end is that you like to do it
for me, i have had enough of calculating all that stuff, i prefer to do it the easy way
still works for me
which reinforces the point : whatever one is happy with

no offense intended btw