Micro Dosing, Am I Thinking it Wrong

Unexpected

Unexpected

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I'm dosing my Macros on the upper side of EI and there are times I front load them and times I do the traditional EI method of 3 doses with 50% water changes. I plan to keep front loading with near 80% water changes because it's simpler to think about, in my opinion, as you remove accumulation totals from the process. But hear me out, I may be a bit discombobulated and hopefully you all can get me sorted.

While front load, I still dose Micros over a set period of days. But I don't think about Micro accumulation totals, I've only thought of them as a set weekly dose. Should I be thinking about the accumulation total? Or stick with the weekly dose total? Why are Micros not front loaded like Macros? Wouldn't front loading them improve stability? Should I dose Micros right after a water change to return the tank to pre change micro levels and continue some smaller doses over the week? How would I determine what those levels were before the water change?

Sorry, I've confused myself too, not just you. 😆
 
Same here, I front load macros after water change but dose micros daily.

The rationale for the macros is convenience (just dose once weekly after WC), but also that the concentrations will be rather stable. If we assume (overdosing using EI) that plants consume generally only a minor part of the macro nutrients, and we avoid accumulation because we do just one weekly dosing and one weekly wc, we can hope for the macro ppm's to be most stable during the week when we do front loading.

For micros the concern is that chemical reactions will not keep them stable and in a form that is available for plant uptake for a full week. For example iron chelators, at higher pH. This is why I dose my micros daily, just before lights on. The micros will also accumulate, if they are not consumed or modified in chemical reactions.

I am not a chemist, so hope that more knowledgeable friends can chime in.
 
So I shouldn't be concerned with the large dip in accumulation total after the water change and just continue as I've always done?
 
Unexpected said:
So I shouldn't be concerned with the large dip in accumulation total after the water change and just continue as I've always done?
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I am just reading that @GreggZ does a triple micros dose after water change, then doses daily until the next WC a week later. This may be a nice compromise that I try as well (in fact I copied my nutrient dosing from @GreggZ tank), between limiting concentration swings from accumulation / water change and daily dosing.
 
Are you following the EI amounts for macros of 7.5/1.3/7.5 per dose 3x week? If so I'd cut NO3 down to about 5 or 6 per dose and up K by about 5-10 per week. The best plant growers today all run K higher than NO3, and nobody needs 40 ppm NO3 in the water (EI @ 50% wc).

Also note that there's a BIG difference in whats actually in your water column based on how much water you change. For example 20 ppm/week of NO3 with 50% water changes will soon be over 40 in the water column due to accumulation (not counting plant uptake, which wont be much) The same 20 ppm a week doing 80% water changes is going to top out about 25 in the water. What this means is the more water you change, the higher your dosing should be as far as the weekly total

As for micros and Fe. Chelated Fe should stick around indefinitely in an available state, as long as youre using the right chelate for your PH level. Fe can somewhat be compared to how macros operate in this regard. The other micros typically dont stick around very long.

Note: Most all retail liquids use non chelated compounds for the lesser micros. Some of the micros In hydroponic/crop blends like csmb, Millers etc usually are chelated with edta (except B and Mo) This changes the game a little bit for the subject at hand. But without going into all that we can still generalize a couple things:

There's a somewhat fine line between good and too much for the lesser micros. You can actually frontload an appropriately-chelated Fe for the whole week if you want to. But you wouldnt necessarily want to do that with the other micros. Also plants dont need a steady supply of these other micros available 24/7. A few 'sips' along the way is all it takes. Things just run better and cleaner when you dont lard them on

So for these two reasons micros are best split into multiple smaller doses.

To the question "Should I dose Micros right after a water change to return the tank to pre change micro levels". Just Fe if you wanted to get technical.
But since most people have micros and Fe together the short answer is, no.

These days I normally change 70-80%. I go right back with a double dose of micros/Fe. This gets Fe off the 'floor' without adding too much of the others. Then about mid week I give it another double dose. Notice also there's an extra dose in there, 4 instead of 3 due to the large volume of water removed, as touched on in the 2nd paragraph up there

Doing 50-60% water changes I like the standard 3x week for both macros and micros. Macros and theoretically Fe can still be front loaded for the entire week.

Daily dosing macros and Fe is best for small water change routines like 25-30%. Changing more than that creates too much of a nutrient swing for daily dosing those. The other micros are not so critical
 
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Burr740 said:
Are you following the EI amounts for macros of 7.5/1.3/7.5 per dose 3x week?
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I'm front loading with 65-80% water changes 28/7/35.

I just received your packets today (great shipping by the way), should I just follow your instructions or try the double dose after water change?
 
Unexpected said:
I'm front loading with 65-80% water changes 28/7/35.

I just received your packets today (great shipping by the way), should I just follow your instructions or try the double dose after water change?
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There's still a big difference in what you wind up with in the water column between 60% and 80%. Best thing is to pick a water change volume and try to be consistent with it. Then base your dosing on that. If you do 80% one week and 60% the next, with the same dosing, you wind up with two totally different water column values. Some plants wont care, some will. Consistency is really important

Doing 50-60% you can just go with the suggested 2 ML per 10 gal dose 3x per week. First one right after the wc.

Doing 80% Id do a double dose right after, then another single dose mid week. Or possibly 2 more single doses every other day. You'll just have to try it and see

The only reason I like big water changes because I sell out of my tanks and plants are constantly getting yanked, moved or trimmed. Under normal circumstances with a clean well-kept tank 50-60% works just fine....and uses less ferts.

If you really wanna save money on ferts and make them last longer change 25-30%. You can dose 1 Ml per 10 gal then and have about the same water column numbers

The whole water change volume thing gets so overlooked. We all wanna know what somebody else is dosing but half the time wc volume isnt even mentioned. Dosing numbers alone are meaningless without knowing that too. "7 ppm 3x week" could mean 25 in the water column (80% wc) or 60! (25% wc)
 
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I'm definitely seeing how far this rabbit hole can go. I was thinking I had a handle on things then I come over here and you guys draw the veil back showing me way more hole. Ugh 😆
 
Agree with everything @burrsaid above.

If you are a glutton for punishment I have some detailed write ups on the effects of water changes and accumulation in my build thread. But you've been warned it's deep in the weeds.

In the end it all has to do with keeping stable parameters. In general plants love stability and hate change.
 
GreggZ said:
Agree with everything @burrsaid above.

If you are a glutton for punishment I have some detailed write ups on the effects of water changes and accumulation in my build thread. But you've been warned it's deep in the weeds.

In the end it all has to do with keeping stable parameters. In general plants love stability and hate change.
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I've been through them a few times and I'm going to permanently remain front loading Macros.

I was talking to burr and late last night double checked my water volume. It looks like I'm nearer to 62-66% water changes. I'm making adjustments today. Fingers crossed!
 
Burr740 said:
Doing 50-60% you can just go with the suggested 2 ML per 10 gal dose 3x per week. First one right after the wc.
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I doubled check my volume numbers again and it's looking like I'm doing between 62-66% changes. Would the 2ml per 10 gallons be total tank volume or 2ml per 10 gallons of water change volume?
 
Yugang said:
I am just reading that @GreggZ does a triple micros dose after water change, then doses daily until the next WC a week later. This may be a nice compromise that I try as well (in fact I copied my nutrient dosing from @GreggZ tank), between limiting concentration swings from accumulation / water change and daily dosing.
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Hi @Yugang

I love to read about GreggZ tank also, as it's one of my favourite planted tanks.

May I ask where you read about Gregg triple dosing micros after a water change? I'm just curious.

Thank you 😊
 
Unexpected said:
I doubled check my volume numbers again and it's looking like I'm doing between 62-66% changes. Would the 2ml per 10 gallons be total tank volume or 2ml per 10 gallons of water change volume?
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The suggested dose for my custom micros of 2 ml per 10 gal is based on the whole tank volume
 
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