Number of doses matter?

K

kb27973

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Hi all,


My tank is currently cycling. The dosing pumps are connected to my controller so I can dose any amount any number of times per day. If I let the controller come up with a program it will do 141 doses at .7ml + 1.3ml once for 100ml/day while at the other extreme I could dump it all in at once. Is there a preference for one way over the other? Off the top of my head I think it would be good to have a constant supply all day vs. one massive dose. But I have under 10 posts so I don't know what I'm talking about. Anyone care to opine on this?


Ken
 

Pikez

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I think one massive dose or two slightly smaller doses are probably OK for macros and GH booster. Everyone is comfortable with adding GH booster once a week. No reason why you cant do that for N, P, and K.


For micros, this may be different, as iron (and possibly other trace minerals) may not remain available for a long time. I'm not sure how long each type of iron remains available, but it may be a good idea to be conservative here and dose every day or every other day.
 
K

kb27973

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Solcielo lawrencia said:
I would prefer more smaller doses rather than one large dose but I have no evidence that one way is better than another.

Exactly what I was thinking, but when I watched it do one of the doses it was literally 4 drops. 4 drops in 150 gallons just doesn't seem like it would do much.
 
K

kb27973

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Pikez said:
I think one massive dose or two slightly smaller doses are probably OK for macros and GH booster. Everyone is comfortable with adding GH booster once a week. No reason why you cant do that for N, P, and K.

For micros, this may be different, as iron (and possibly other trace minerals) may not remain available for a long time. I'm not sure how long each type of iron remains available, but it may be a good idea to be conservative here and dose every day or every other day.

The way I'll be dosing (per directions) is 130ml/day - MWF Macros, TTS Micro, Sunday water change.


I'm more asking about does it matter over the course of a single day. Maybe I'm overthinking this, but I have this controller that will do whatever I tell it to so I might as well tell it to do the right thing.


Do plants uptake any macro/micro ferts at night? If they don't I'm basically polluting the water by dosing at night so maybe I should dose only during light period?
 

UDGags

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Just be consistent with the same time every day for macros and micros..


For micros I usually do it 1-2 hours after light/CO2 comes on since that is when they will be needing the nutrients. Not sure what type of iron chelate you have but they won't last very long in water typically.
 
K

kb27973

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UDGags said:
Just be consistent with the same time every day for macros and micros..

For micros I usually do it 1-2 hours after light/CO2 comes on since that is when they will be needing the nutrients. Not sure what type of iron chelate you have but they won't last very long in water typically.

So you just dump it all in at once for the day? It's looking like it probably doesn't matter. I'll probably have it dose multiple times during the daylight hours and none at night and see how that works.
 

Marcel G

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If you dose nutrients once per week, in water there will be higher momentary concentration, and higher "overpressure". In other words, higher external concentratin of nutrients leads to higher nutrient uptake rates. So in this sense, higher is better. BUT be aware that each plant species has its optimum external concentration of nutrients, so what may be good for one plant species may be too much for others. For example, according to my growth experiments Pogostemon erectus has its optimum under 15 ppm NO3. Also, as Pikez poited out in his first post, micronutrients won't usually last very long under our normal aquarium conditions (especially iron chelates). Fe-gluconate will last no more than 1 day. The same is usually true for Fe-EDTA. The best Fe-chelate for our use (in my opinion) is Fe-DTPA. This chelate will last for at least 5 days (or even more) before it breaks down and let iron to meet his inevitable fate (which is precipitation). Chelates degrade not only under higher pH, but under normal room temperature and light also. So right after you add them to your tank, the chelate will begin to loosen some iron (and this iron will immediately oxidate). So for iron it is always wise to dose it as frequent as you can (optimally on daily basis); in case you use a stronger chelate like Fe-DTPA you can afford to dose it once a week.


Still, what you should consider (before adding too much nutrients into your aquarium water) is that for aquatic organisms (fish, invertebrates, small critters, and microbes) the water quality and purity is of utmost importance. Many developmental stages of fish and shrimps are very sensitive to higher nutrient concentrations in water. Adult fish may be fine with quite a high nutrient concentrations in water, but not so the fry or fish eggs.


So on the one hand you have your plants for which it may be better to dose higher concentrations of nutrients, but on the other hand you have there also fish which may like rather much smaller nutrient levels. The best way to solve this conflict is to use a nutrient rich substrate. In such a case you don't need to dose nutrients into water column (except some smaller amounts of Ca, Mg, K which plants prefer to take up from water column).
 
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K

kb27973

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Marcel G said:
If you dose nutrients once per week, in water there will be higher momentary concentration, and higher "overpressure". In other words, higher external concentratin of nutrients leads to higher nutrient uptake rates. So in this sense, higher is better. BUT be aware that each plant species has its optimum external concentration of nutrients, so what may be good for one plant species may be too much for others. For example, according to my growth experiments Pogostemon erectus has its optimum under 15 ppm NO3. Also, as Pikez poited out in his first post, micronutrients won't usually last very long under our normal aquarium conditions (especially iron chelates). Fe-gluconate will last no more than 1 day. The same is usually true for Fe-EDTA. The best Fe-chelate for our use (in my opinion) is Fe-DTPA. This chelate will last for at least 5 days (or even more) before it breaks down and let iron to meet his inevitable fate (which is precipitation). Chelates degrade not only under higher pH, but under normal room temperature and light also. So right after you add them to your tank, the chelate will begin to loosen some iron (and this iron will immediately oxidate). So for iron it is always wise to dose it as frequent as you can (optimally on daily basis); in case you use a stronger chelate like Fe-DTPA you can afford to dose it once a week.

Still, what you should consider (before adding too much nutrients into your aquarium water) is that for aquatic organisms (fish, invertebrates, small critters, and microbes) the water quality and purity is of utmost importance. Many developmental stages of fish and shrimps are very sensitive to higher nutrient concentrations in water. Adult fish may be fine with quite a high nutrient concentrations in water, but not so the fry or fish eggs.


So on the one hand you have your plants for which it may be better to dose higher concentrations of nutrients, but on the other hand you have there also fish which may like rather much smaller nutrient levels. The best way to solve this conflict is to use a nutrient rich substrate. In such a case you don't need to dose nutrients into water column (except some smaller amounts of Ca, Mg, K which plants prefer to take up from water column).

Makes sense. So the optimum would be to dose the entire days 130ml right when the lights come or maybe shortly after?


Also, it looks like I have a big problem with the way I'm dosing. Last weekend I started the dosing. I filled the container with a weeks worth just to get a feel for things, but when I have it down I was planning on filling the dosing reservoir which would last about a month. But from what you said above is all my iron unusable after a single day? Does everybody mix ferts daily?


PS - The iron in my ferts is EDTA.
 
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It's better to dose a small amount multiple times per day than all at once.


If FeEDTA is in a prepared solution, it won't unbind from its chelator because there's nothing competing for it and nothing else to bind to. Only when it's in the presence of certain chemicals, especially phosphate, will it break.
 

Marcel G

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Solcielo lawrencia said:
If FeEDTA is in a prepared solution, it won't unbind from its chelator because there's nothing competing for it and nothing else to bind to. Only when it's in the presence of certain chemicals, especially phosphate, will it break.
I think that this is true just in part. While it's true that if there are no anions (like phosphates or hydroxides) in the stock solution which may bind with unchelated iron cations, still there will be some oxygen which will oxidate the iron into Fe+3 (in case it was in Fe+2 form in the chelate originally). So the result will be a stock solution with broken down chelate complex with the oxidized iron in the solution. Once you add this solution to the aquarium, the oxidized iron will immediatelly become unavailable to plants (although in part it can bind back to some natural chelating agents in your tank - like humic substances or dissolved organics). The problem is that there is also temperature and light at play in chelates degradation. At room temperature and light illumination the weaker chelates will break down even if there are no anions which may bind with the loosen iron in solution. So from this reason, it's always a good idea to store the stock solution in the fridge (dark + very low temperature). In case of Fe-gluconate or Fe-EDTA I would add some acid into the stock solution also to keep the pH low.


"kb27973" if you want to find out whether your iron stays in chelated form for a longer time, you can make a little experiment in some small empty tank. Add a couple of small, healthy plants in small flower pots into this tank. Ensure the water will circulate (at least a little). You can use some small internal filter (but don't use any filter media in it). Also use just plain gravel, not any soil or clay substrate in the flower pots (as these will quicly absorb the iron from water). Put some light source over this small tank. Then dose the iron as usual into this tank (but don't forget to adjust the dose for smaller water volume!). The next day you'll see if the iron precipitates or not. In an empty tank the precipitation is clearly visible (especially on plants). Best plants to use in this experiment are Pogostemon erectus or Rotala wallichii (or a similar plants with very fine needle-like leaves).
 
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K

kb27973

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Marcel G said:
"kb27973" if you want to find out whether your iron stays in chelated form for a longer time, you can make a little experiment in some small empty tank. Add a couple of small, healthy plants in small flower pots into this tank. Ensure the water will circulate (at least a little). You can use some small internal filter (but don't use any filter media in it). Also use just plain gravel, not any soil or clay substrate in the flower pots (as these will quicly absorb the iron from water). Put some light source over this small tank. Then dose the iron as usual into this tank (but don't forget to adjust the dose for smaller water volume!). The next day you'll see if the iron precipitates or not. In an empty tank the precipitation is clearly visible (especially on plants). Best plants to use in this experiment are Pogostemon erectus or Rotala wallichii (or a similar plants with very fine needle-like leaves).

Thanks Marcel. Sounds like an interesting experiment. I'm still very new to this so may try that once I get the main tank running smoothly.


I ordered a dry fert 'kit'. If I follow the instructions I'll be dosing approx.: Iron (Fe) 0.5ppm per week. My dosing schedule now is 130ml/day (142 doses from midnight to midnight) in a 150G tank. MWF - macro, TTS - micro, sunday water change. So If I've followed the conversation I should dose half shortly after lights come on and the other half midday when light intensity is highest. Macro's I can store for multiple days (weeks?), micros need to mix fresh daily. I do have the dosing containers sitting on stirrers which stir a couple of times a day. No idea if this helps but I had an extra stirrer from my reef tank. Was just thinking if it was sitting there for weeks may help. Is there anything that can be added to the micro mix to keep iron in a usable state for longer? I really would like to mix ferts weekly (or monthly!).


Ken
 
K

kb27973

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Solcielo lawrencia said:
It's better to dose a small amount multiple times per day than all at once.

I agree. I let the controller set up the schedule and I think it went a little over the top with 142 doses. So if you had a controller and could schedule any time and number of times how would you dose 130ml/day? With micro and macro being dosed on alternate days.


Ken
 

UDGags

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kb27973 said:
So you just dump it all in at once for the day? It's looking like it probably doesn't matter. I'll probably have it dose multiple times during the daylight hours and none at night and see how that works.

Personally, I put in the solid powder into my sump and let it dissolve in there and get pumped throughout the tank. I did macros in the morning and micros in the evenings when lights had been on for 2hrs (8hr cycle). If I had a small peristaltic pump like you have I would spread out the micro's throughout the light cycle. Macro's I would just be consistent. You just want to avoid huge swings in concentrations.


Dosing powder was simple for me since I pre-weighed it out in baggies on weekends and just dumped it in.
 

Tom Barr

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I dose the macros 2x a week.


Traces, as often as daily if I remember.


This does not seem to cause any issues with any species(which is a lot if not most you have seen in aquariums) I've kept to date.


Now I just got back from being away for a week and some plant are a tad pale............more N limited and Trace limited than anything.


Still, they are okay and recover in a few days. If I leave for say 2 weeks.......then you get more pronounced changes.


Note, this assumes they are in good shape prior to leaving and a sediment rich in nutrients will offer a significant back up.


So something like ADA aqua soil might be a wise thing for some folks. Myself included.


Every so often, dosing pumps are on sale, so you can do that also. I've done the daily thing, then dosing pumps are on client tanks, and then I use to do 3x a week, then cut it to 2x a week.


2x a week seems to be about the min for CO2 enriched systems to get decent results.
 
K

kb27973

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UDGags said:
Personally, I put in the solid powder into my sump and let it dissolve in there and get pumped throughout the tank. I did macros in the morning and micros in the evenings when lights had been on for 2hrs (8hr cycle). If I had a small peristaltic pump like you have I would spread out the micro's throughout the light cycle. Macro's I would just be consistent. You just want to avoid huge swings in concentrations.


Dosing powder was simple for me since I pre-weighed it out in baggies on weekends and just dumped it in.

Yet another way to dose ferts.. :) Makes sense what you said about trying not to have large swings. I think the controller thinks that way too as it was doing 140 doses per day to dose 130ml. I'm thinking I'll have it dose every 4 hours for the macros throughout the whole 24 hours and for the micros I'll have it dose alternate days during the light cycle. Any particular reason micros are during the light cycle only?
 
K

kb27973

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Tom Barr said:
I dose the macros 2x a week.
Traces, as often as daily if I remember.


This does not seem to cause any issues with any species(which is a lot if not most you have seen in aquariums) I've kept to date.


Now I just got back from being away for a week and some plant are a tad pale............more N limited and Trace limited than anything.


Still, they are okay and recover in a few days. If I leave for say 2 weeks.......then you get more pronounced changes.


Note, this assumes they are in good shape prior to leaving and a sediment rich in nutrients will offer a significant back up.


So something like ADA aqua soil might be a wise thing for some folks. Myself included.


Every so often, dosing pumps are on sale, so you can do that also. I've done the daily thing, then dosing pumps are on client tanks, and then I use to do 3x a week, then cut it to 2x a week.


2x a week seems to be about the min for CO2 enriched systems to get decent results.

From what I can see there is really no standard way to dose. Whatever fits in your schedule (and tank) I guess.


I do have a couple of dosing pumps and a controller. My plan was to fill the macro/micro containers monthly but it seems like my iron will change form and be unusable after a day. Is there any way around mixing micros daily?
 

Tom Barr

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Obviously, not all tanks are the same. But neither are all aquarist goals.


Ponder that for a moment.


So....this logic might lead you to think: no one dosing method/routines will meet all goals either.


Some plant tanks will be much more demanding while others seem to run themselves.


More light, overstocked/fed, more stem plants, shallower tanks that need more trimming, trimming methods, sediment type, filtration etc, all play roles.


My 70 Gallon Buce tank is easy to care for, the 120, not so much, I have about 2x the light and lots of stem plants in the 120.


My plants and goals and light are different.


I can get away with much less care on the 70 gallon......but clearly, not everyone wants a tree like Buce covered tank..........


Nor does everyone want 2x a week water change and trim routine on a high light stem tank.
 
K

kb27973

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Tom Barr said:
Obviously, not all tanks are the same. But neither are all aquarist goals.
Ponder that for a moment.


So....this logic might lead you to think: no one dosing method/routines will meet all goals either.


Some plant tanks will be much more demanding while others seem to run themselves.


More light, overstocked/fed, more stem plants, shallower tanks that need more trimming, trimming methods, sediment type, filtration etc, all play roles.


My 70 Gallon Buce tank is easy to care for, the 120, not so much, I have about 2x the light and lots of stem plants in the 120.


My plants and goals and light are different.


I can get away with much less care on the 70 gallon......but clearly, not everyone wants a tree like Buce covered tank..........


Nor does everyone want 2x a week water change and trim routine on a high light stem tank.

Couldn't agree more. I'm very new to planted aquaria (ex reefer though), but am doing a lot of reading. Things are progressing well in my 20 day old tank - I think. I just started dosing ferts last week and I have this extremely configurable dosing system. I let the controller pic the dosing of 130ml/day and it chose to do it in over a hundred small doses. Since I can do anything from one massive dose to 100+ small doses - does it matter? Seems like it should as I would think plants would be using at a faster rate during the day vs night. So would it be better to only be dosing during light hours? That started a conversation on iron stability. The bad news I got out that is if you store iron for more than a day it is no longer usable. That means I would have been dosing 'good' iron one day a month since I would have a month supply in the dosing tank. If I'm making a mountain out of a molehill here please feel free to let me know. I'm just surprised this hasn't come up more often with the technology out there for dosing.