Lean dosing pros and cons

[MichaelJ]

maybe we need to collect some data points? Here's mine

I am not entirely sure what the final data points is going to be for me. But the particular low-tech tank (40 US Gallon / 150 L) I am going to use for the high light experiment is currently:

Starting point is 100% RO+DI water degassed for about 24 hours.

KH ~1 from K2CO3
GH ~4.75 (Ca 24 ppm / Mg 6 ppm) Ca Gluconate, MgSO4 and a tiny bit of CaCl2 (for the trace amount of Cl). Mg from Mg Gluconate and Mg(NO3)2).
pH is in the 6.2-6.5 range
Temperature 75 F / 24 C (very stable all year around)
Photoperiod +12 hours at low light intensity (my tanks are in a room with very low levels of ambient or daylight exposure)

NO3 15.33 from Mg(NO3)2
PO4 4.60 from KH2PO4
K 18.0 from K2CO3 and KH2PO4

Fe 1.0 ppm from EDTA (Nilocg Plantex CSM+B traces)
Fe 0.25 from Fe Gluconate

All the minerals and macros are mixed in with the weekly ~40% WC. Traces are split into two weekly doses (1st on the day after WC and the 2nd mid week).

Stocking is fairly light (Tetra's and Oto's).

Of course, I will (probably) have to tweak the above for the high light experiment. Otherwise, I expect I can keep in my substrate and just replace a ton of plant and crank the light waay up! (against my own advice )

Cheers,
Michael

 

[Sudipta]

Welcome @Sudipta - enjoyed reading your thread over at TPT before it got binned, and looking forward to the further data you'll add to the UKAPS hive mind with your journal.

I will confess up front to total selfishness in welcoming you - I'm running 3 low tech tanks at the moment, the most recent of which (journal to come, eventually) is just maturing. First cherry shrimp went in last weekend. It's room temperature (20-22 in the winter, 22-25 in the summer) currently 2/3 rainwater 1/3 tapwater which gets it down to 110 TDS.
I'm ambling gently towards the lean route (currently upped the K, dropped the NO3 and added a smidge of Urea) and will be using that tank as my test bed. This feels like an opportunity to maybe see if I can add an extra data point to the info pool. I'm more than happy to drop the TDS further (my rainwater tests at 12, so that's as low as I can go). My caveats are: (1) will Shrimp still be happy? (2) I can't do more than 20 L of rainwater in any given WC (tank is 70L), and (3) I can't guarantee 7 day WCs - sometimes they're 8 days, sometimes 9, sometimes 6. I unfortunately have this annoying 'rest of my life' thing that keeps getting in the way. Which is why I'm low tech; more forgiving. Would doing just rainwater, remineralizing with an appropriate amount of tap (330 TDS) water be a sufficient baseline to use for a meaningful experiment?

Cheers,
Simon

Hello Simon,
Thank you for appreciation. The thread at TPT got restored again, I was told that it was caught in some kind of spam filter or so. I don't know what to say but it is back which I am happy about. Since I have already started the thread over there, I will try to give more updates as time would allow. However, I am also considering to create another thread in this forum, so it will serve as a backup and I will be able to reach more people and answer more questions. This will allow me to investigate more about my own system and I might find new information while trying to answer questions.
If your system is working properly then there is no need to change anything in my opinion. TDS alone doesn't tell anything about the actual components (GH, KH etc.), so it is hard for me to speculate about the ratio of rain and tap water and its outcome. Although most plants and fishes/shrimps are quite adaptable when it comes to GH but high KH is particularly a big problem for most plants as I have mentioned in my thread at TPT. Cherry shrimps are quite forgiving from my experience, I was able to breed them in a tank with low PH (less than 6, almost 0 KH), however the breeding rate was quite slow in those parameters as compared to caridina shrimps. The TDS was about 110-130 and it was primarily coming from Salty shrimp GH+ (mainly Ca and Mg). I do have golden back yellow shrimps in a tank (shown below) where I use just tap water, pH about 7.4, KH; 3-4, GH; 6-7, TDS; 120-140. I do let the water sit in a bucket for at least overnight with Seachem prime before water change. I try to do weekly water change in all of my tanks but it is not absolutely necessary to follow the exact routine. These systems are very slow, so even if you miss one or two weeks it won't affect the system that much, unless you are constantly delaying maintenance. one or two days here and there won't affect anything (from my experience).
I don't know if I was able to properly answer your questions.

 

[Hufsa]

The thread at TPT got restored again, I was told that it was caught in some kind of spam filter or so. I don't know what to say but it is back which I am happy about. Since I have already started the thread over there, I will try to give more updates as time would allow. However, I am also considering to create another thread in this forum, so it will serve as a backup and I will be able to reach more people and answer more questions.

I hope you will keep a backup of your writings on TPT or if possible to reconsider writing your thread here. It appears that the moderator has removed the entirety of Greggz journal, when I tried to access it this morning it was gone. Such a large source of knowledge gone, seemingly out of spite I do not wish the same thing to happen to you should you accidentally say something the moderator doesn't agree with 😕

 

[Sudipta]

Disclaimer: This post is not directed at any one person 😃

Learning is not a process you can finish. No matter who you are, no matter if its the aquarium hobby or something else.
If a person thinks they have got everything entirely figured out, their mind is closed and no learning will happen.

One can agree to disagree, I think this is important to remember.
There appears to be more than one way to grow plants, which explains why very different methods can achieve such great results.
A friendly tone and the shared desire for knowledge can form a bridge over quite large gaps.
The focus on this is (in my opinion) one of the things that makes UKAPS great 😄

Im very happy to welcome our new members, it is evident they hold a great deal of knowledge and I look forward to learning from them!

Very well said. I absolutely agree with you. As I mentioned in my thread at TPT, I was really struggling to keep couple of species happy in my CO2 injected tank and they were constantly getting covered with algae. I moved them to my softwater non-CO2 supplemented tank as per my friend's suggestion that there is nothing to loose to give it shot. To my surprise, both of those two species started to grow (at very slow speed) and eventually I was able to propagate both of them. It has been more than two years since I started growing Rotala wallichii and Ludwigia senegalensis in non-CO2 supplemented softwater tank and both of them stay relatively happy for most of the time in this system.

Since then, I slowly started experimenting with other so called difficult plants (mainly stem plants) in these systems which according to many "experts", absolutely need pressurized CO2 injection and as of now I am able to grow many such species with decent form and health for significantly longer period of time.

I just want to clarify again that I am not comparing their growth form and color to CO2 injected tanks, obviously they will look much better in hightech environment. However, I am quite happy with the results that I am getting without pressurized CO2 injection and I will continue to do so.
Thanks,
Sudipta.

 

[Sudipta]

I hope you will keep a backup of your writings on TPT or if possible to reconsider writing your thread here. It appears that the moderator has removed the entirety of Greggz journal, when I tried to access it this morning it was gone. Such a large source of knowledge gone, seemingly out of spite I do not wish the same thing to happen to you should you accidentally say something the moderator doesn't agree with 😕

Thank you for the suggestion. I will definitely keep a backup after what happened to Gregg. This is really a shame.
I am also thinking about starting a new thread here soon.

 

[plantnoobdude]

things are going pretty well.
tank is at
1ppm N ( ~4ppm No3)
0.13ppm P (0.39ppm po4)
0.66ppm K
keep in mind I have relatively new soil.
and micros have been changed recently to half non Fe micros and same amount of iron. because im seeing what I believe is induced fe deficiency in some plants.
now it is
0.1ppm Fe dtpa
0.0335Mn
0.007 Zn
0.007 B
0.0035 Cu
0.00015 Mo
0.00005 Ni
Iron level is staying the same just the rest of the micros that are changing, if this works, then It'll be the first time i've seen the effect of ratios in my tank. exciting times.
current plants doing well:
macrandra, rotala indica, ludwigia cuba, tonina.
struggling plants:
cuphea, rotala wallichii, s repens.
water changes every two weeks, tds is 100

 

[Happi]

Mmm, could be wrong hopefully @Happi Will correct me on this but suspect lean dosing works better when the ph and kh are low?

Just throwing it out there 🤪

that is Correct John, the lean dosing approach works better when the KH is almost 0, because under such scenario the reaction and precipitations of the nutrients are significantly reduced.

what michael said is spot on.
View attachment 183995
if you take a look at mulders chart, you will see that various hard water nutrients that come with kh, Ca, Mg, K....
inhibit uptake of other nutrients, Ca for example doesn't improve uptake of any nutrients. so having it in excess can mean you have to dose more micros, I believe @Happi has had this experience and can confirm.

I use these chart for reference only, under the water they might produce different results, this chart becomes more accurate when there is too much CO3 in the water. its not only too much Ca that inhibit the uptake, but CO3 if present at the same time in higher amount. other nutrients will interact the same way with each others depending on the presence of Co3, Ph, KH etc. the higher they are, what you see in the chart will surely occur.

Based on the Marchner ratio and the Recipe that we used, this chart is quite accurate.

 

[Happi]

Things where I stand with @Sudipta based on my own Experiments:

• Use RO/DI water
• Low to 0 KH
• Lean water Colum dosing
• Acidic Soil Enriched with NH4
• High Lights ( I use lights rich in Red and Blue spectrum, not sure about Sudipta )
• Low Co2

Things Where I still might have different opinion:

• Will this approach only work for Aqua soil or will it work with Inert substrate? It should if NH4 was applied in the water at smaller amount while reducing the amount of NO3 present in the water.
• Higher GH? Probably not needed but it can be beneficial if Micro were to buildup over time.
• Low Temperature? This seems to be the major factor for Sudipta success, from the chemistry point of view he is not wrong about Co2 being more dissolved. But we will need to further investigate if temp of 70 F or so is the only way to accomplish this goal.

So we can safely say that point 1-6 are the key factors, additionally adding cold temp for Non Co2 seems to be the major key factor as well in Sudipta case. If we were to apply the 1-6 with somewhere between the colder and warm temperatures, something like 74 F, I don’t see why it wouldn’t work, even though 1-6 were working just fine for me even at 76-78 F while adding 15-20 ppm CO2. 70 F might be too cold for some plant sp. but 74 F might be more tolerable.

Something like this:

70 F, Non Co2

72 F, 5-10 ppm Co2

74 F, 10-20 ppm Co2

combine the above information and try it with lower co2 as suggested. Using RO/DI water gives you better control, so during this experiment I would advise against using tap water even if it were to be low in KH. But you will have option to explore that as well once you master this one. far as the nutrients goes it has already been advised.

 

[Sudipta]

Things where I stand with @Sudipta based on my own Experiments:

• Use RO/DI water
• Low to 0 KH
• Lean water Colum dosing
• Acidic Soil Enriched with NH4
• High Lights ( I use lights rich in Red and Blue spectrum, not sure about Sudipta )
• Low Co2

Things Where I still might have different opinion:

• Will this approach only work for Aqua soil or will it work with Inert substrate? It should if NH4 was applied in the water at smaller amount while reducing the amount of NO3 present in the water.
• Higher GH? Probably not needed but it can be beneficial if Micro were to buildup over time.
• Low Temperature? This seems to be the major factor for Sudipta success, from the chemistry point of view he is not wrong about Co2 being more dissolved. But we will need to further investigate if temp of 70 F or so is the only way to accomplish this goal.

So we can safely say that point 1-6 are the key factors, additionally adding cold temp for Non Co2 seems to be the major key factor as well in Sudipta case. If we were to apply the 1-6 with somewhere between the colder and warm temperatures, something like 74 F, I don’t see why it wouldn’t work, even though 1-6 were working just fine for me even at 76-78 F while adding 15-20 ppm CO2. 70 F might be too cold for some plant sp. but 74 F might be more tolerable.

Something like this:

70 F, Non Co2

72 F, 5-10 ppm Co2

74 F, 10-20 ppm Co2

combine the above information and try it with lower co2 as suggested. Using RO/DI water gives you better control, so during this experiment I would advise against using tap water even if it were to be low in KH. But you will have option to explore that as well once you master this one. far as the nutrients goes it has already been advised.

Thanks @Happi for the nice summary.
I just want to clarify couple of things regarding my setups because I was probably not clear enough in my description at TPT thread.
1. Light - I am using lights rich in red and blue spectrum (various Chihiros models for all 4 of them).

2. Temperature - I wrote in my TPT thread that I see better results at low 70F (I didn't mean an exact number - 70F), I was trying to refer the lower range of 70F (70-75F). I don't think that my observation skills are good enough to see any noticeable difference in plant health in that range. It becomes more noticeable to be when the temperature starts to get higher than 76F, close to 80F and beyond. I am really sorry for this confusion.
I just measured the temperature using a cheap tds meter for all of my non-CO2 supplemented softwater tanks as shown below.

3.Substarte - I do think that soil based substrate will give the best result because I think the majority of CO2 is coming from the sediment. I can't prove it right now but based on what I know, the atmospheric CO2 dissolution is almost negligible at these conditions (less than 1 ppm, probably close to 0.5 ppm). I believe the organic components of soil are getting decomposed by microbes and providing majority of CO2 for these systems. Lower pH (low KH) along with lower temperature are helping in this regard as well.

Thanks,
Sudipta.

 

[Happi]

@Sudipta

the co2 from decomposing is a valid point, this remind of Diana Walstand when you said that. in a sense you are almost running a Diana Walstad approach just with very strong lights.

 

[plantnoobdude]

Diana Walstand when you said that.

me too, I need to try find the part where she talked about it.(maybe tomorrow) she also found co2 levels changing throughout photo period like sudipta.

 

[Sudipta]

@Sudipta

the co2 from decomposing is a valid point, this remind of Diana Walstand when you said that. in a sense you are almost running a Diana Walstad approach just with very strong lights.

Actually there are several differences between her system and mine other than light.
1. I am specifically keeping my tanks at very low KH (undetectable using commonly available kits).
2. I am also trying my best to keep the temperature lower.
3. I am using filters with decent flow in all of my tanks.
4. Although I am using soil based substrate but none of these are extremely high in organics (like organic potting mix that she recommended). It will give good results for several months but higher organics will lead to more algae problems in the long run as it compacts with time.
5. I am performing regular water changes unlike her method. I always perform the water change during the light period (1-2 hours after lights turn on). I think this also benefits plants especially during warmer months as new water is usually colder than tank water and it also exposes some taller plants to the air for short period of time. So frequent water changes ( just 15-20% water change should do the trick) during summer months will give better results (I have done it in the past and I know it works).

 

[Maf 2500]

In part this approach is replicating the system that exists in nature where rivers have much more CO2 than equilibrium due to terrestial organic carbon being washed into the water and then converted by micro-organisms into CO2.

Not sure if this paper has been referenced earlier in the thread but will link it anyway:
Carbon in catchments: connecting terrestrial carbon losses with aquatic metabolism

 

[Sudipta]

In part this approach is replicating the system that exists in nature where rivers have much more CO2 than equilibrium due to terrestial organic carbon being washed into the water and then converted by micro-organisms into CO2.

Not sure if this paper has been referenced earlier in the thread but will link it anyway:
Carbon in catchments: connecting terrestrial carbon losses with aquatic metabolism

Yes you are right. Although I have not read this exact article but I have found several papers showing strong correlation between doc and CO2 production in river systems.

 

[Happi]

@Sudipta you have mentioned that you had issue with high tech setup with co2 and fertilizer. Can you shine more lights on this?
Why you think there are less issues with non co2 tank? Because most people if they were to run high lights without co2 would have ended up with tons of algae.

 

[Happi]

Actually there are several differences between her system and mine other than light.
1. I am specifically keeping my tanks at very low KH (undetectable using commonly available kits).
2. I am also trying my best to keep the temperature lower.
3. I am using filters with decent flow in all of my tanks.
4. Although I am using soil based substrate but none of these are extremely high in organics (like organic potting mix that she recommended). It will give good results for several months but higher organics will lead to more algae problems in the long run as it compacts with time.
5. I am performing regular water changes unlike her method. I always perform the water change during the light period (1-2 hours after lights turn on). I think this also benefits plants especially during warmer months as new water is usually colder than tank water and it also exposes some taller plants to the air for short period of time. So frequent water changes ( just 15-20% water change should do the trick) during summer months will give better results (I have done it in the past and I know it works).

I see your point but many people do run filter, heater, perform water changes etc. With Diana walstad methods. Aqua soil is also rich is organic matters similar to organic soil but ofcource the organic soil will decompose rather quickly compared to aqua soil. But I understand your point, looking forward to hear more from you.

We have data from some rivers from the south somewhere buried in this thread where there is a difference between the co2 levels.

 

[Happi]

Found it

 

[JacksonL]

New fert batch day so I can add my numbers as a data point
Liquid fert dosing weekly ppms (micros delivered in one dose every day and macros split over 8 doses every day)
N 1.8ppm (8ppm NO3) half from urea half from KNO3
P 0.16ppm (0.5ppm PO4) *worried this is a bit low, would love comments from those experienced in lean dosing!
K 2.73
Fe 0.3
Mn 0.04
Zn 0.022
B 0.018
Cu 0.004
Mo 0.0042
Co 0.001
Ni 0.001

I currently do 50% water changes weekly with remineralised RO, I use epson salts, CaCl and potassium carbonate.
water change water has the following values:
dKH 2
dGH 5.5
Ca 28.5
Mg 6
K 27.84

wondering if it would be worth slowly bringing the dKH value down with each water change which would also result in lowering the amount of K I am putting in each week?
if so how slowly/quickly would I be able to start reducing that?

also should add, tank is 60L of actual water, runs CO2 (1 PH drop from degassed water) with 2x t5HO’s over it.

 

[plantnoobdude]

New fert batch day so I can add my numbers as a data point
Liquid fert dosing weekly ppms (micros delivered in one dose every day and macros split over 8 doses every day)
N 1.8ppm (8ppm NO3) half from urea half from KNO3
P 0.16ppm (0.5ppm PO4) *worried this is a bit low, would love comments from those experienced in lean dosing!
K 2.73
Fe 0.3
Mn 0.04
Zn 0.022
B 0.018
Cu 0.004
Mo 0.0042
Co 0.001
Ni 0.001

I currently do 50% water changes weekly with remineralised RO, I use epson salts, CaCl and potassium carbonate.
water change water has the following values:
dKH 2
dGH 5.5
Ca 28.5
Mg 6
K 27.84

wondering if it would be worth slowly bringing the dKH value down with each water change which would also result in lowering the amount of K I am putting in each week?
if so how slowly/quickly would I be able to start reducing that?

also should add, tank is 60L of actual water, runs CO2 (1 PH drop from degassed water) with 2x t5HO’s over it.

I dont see the need for kh. reducing K and kh should help the tank. 3-4ppm K weekly is more than enough. 0.66ppm works as well. you can probably reduce gh to 4 even with your shrimps.
that po4 level should be fine, but if you want to follow marschner ratio. raise it to maybe 0.24ppm P. as for micros this is from csmb? i would suggest making your own. I had very good results from just changing my micros. happis tenso clone works very well, and you can adjust it from there.

 

[JacksonL]

I dont see the need for kh. reducing K and kh should help the tank. 3-4ppm K weekly is more than enough. 0.66ppm works as well. you can probably reduce gh to 4 even with your shrimps.
that po4 level should be fine, but if you want to follow marschner ratio. raise it to maybe 0.24ppm P. as for micros this is from csmb? i would suggest making your own. I had very good results from just changing my micros. happis tenso clone works very well, and you can adjust it from there.

Unfortunately the salts for DIY micros are extremely hard to come by in small enough quantities in Australia to make it viable. I have switched over to Yara Rexolin (same manufacturer as Tenso) and added in my own nickel. I am also using 13% EDTA Fe to add a different chelator (Rexolin is DTPA) and keep micro numbers down/closer to tenso numbers.