Hi all,
The title isn't the whole question, it's far more complicated the issues I am having but I think I have a fair idea of the right path, hopefully, I guess that's why I am here to ask if my hypothesis is in the ball park.
So anyway, my setup currently is a non co2 temperate low light tank with two pretty large axolotls. The tank is 122 x 35.5 x 50ish cm, so a non standard 4' and a fraction of an inch size. Yeah, I had to custom order a custom made tank to replace this one soon as it is damaged, 4th or 20th owner, who knows, I'd say it's from the 90s
The substrate unfortunately is just quartz play sand from the hardware store (Bunnings for fellow Aussies), long story but FB groups steered me in all the wrong directions).
I have all the stuff to setup the replacement tank in the new year using the Barr non co2 method, but for now I am learning all the ways I can break stuff on this one.
The plants are mainly hygros, Polysperma, Corymbosa, a single sword, two anubias, recently added microsorum to a drift wood piece, and two normal pond lillies.
There is some small amount of java moss too, but nothing signifcant.
I have floaters, heaps of duckweed, fair amount of red root, and surprise water spangles, only just starting to spread.
So here in Aus, ferts are all crap, impossible to get anything good. So many months ago I went the macro way of dry salts from a chemical shop and was also lucky enough to be able to get KNO3 which was silently banded here for a good few decades but now relaxed laws allows you to gt basic chemicals again.
Macros are a non issue.
KH2PO4 every two weeks and maintain about 2ppm
CaCl and MgSO4 for the GH upon WC, sometimes a top up after several weeks, just drops maybe 1 GH over that time.
KNO3, barely ever use it, bio-load is more than high enough. Just sometimes after a WC to bring the NO3 back to range as it can take about two weeks for it to naturally go high enough.
K2SO4 for K, just once upon WC, never really moves for months
Water parameters are:
160L total
18.5c
Ph 6.5
GH 7-8 at Ca to Mg of 2.5:1
KH 1.5
K, 30ppm
NO3 25ppm
PO4 2ppm
TDS 250-300 ppm normally
Fe try to dose up to 0.1 0.2ppm total, split bi-weekly atm. Normally always detectable in Fe test. Used to go as high as 0.4ppm but micro mix nuked the plants.
Light, Beamswork Vivio, low light type of thing, full spec., 10 hours.
WC, only after 2-3 months when the tank is full of mulum.
Micros I tried many, seachem ones were so weak that literally no change, even at like 4x the dose. No change what so ever. Iron test always showed zero iron despite dosing saying otherwise.
Tried the Equilibrium, kinda worked but needed way more than the Barr method and ended up with too much everything else, but no OD symptoms, just went to deficiency if I stopped dosing as much or as often, never got the deficiency sorted like I wanted. I think that needs the the substrate outlined in the method for this to work well, inert sand doesn't cooperate.
Purchased AquaForest Micro, all suppliers in Aus were not able to get it and my one I purchased got lost in the mail. So I ended up being given a refund. Still can't get that.
After looking for something unrelated I found LCA micro mix from LCA in QLD Aus, and yeah that's when the problems started but at the same time also helped my floaters finally grow.
I was dosing to about 0.2ppm of Fe that the proxy said. Eventually I found out that the ratios are way off and they had something 4-6x the Mn and Zinc and Cu over the iron.
So I thought, ok, that was my prob.
The problem was all my hygros stopped growing, got symptoms of severe K difference, Mn/Mg/Fe like symptoms, N symptoms, and all the old leaves fell off over a few days, some of the new leaves and the middle ones seemed to be ok but a bit holey. Nothing wanted to grow.
However, the floated actually took off but the frog bit seemed to fuss. Less micros, they got square holes in them, more micros, they corrected but all the other plants below start dying.
The red roots also showed better color and growth with more micros.
Interestingly, my macros went up and Fe levels stopped going down, so the toxicity blocked all uptake it seemed.
LCA micro mix link here, and yeah, not good ratios and dose suggested a crazy high too. I dosed half the dosing from get go and half a frequent, and even reduced it more when this was happening.
www.liverpoolcreekaquariums.com.au
So I bought some Rexolin, did a 90% WC, left it for 2 weeks and started again.
This time I dosed to 0.08ppm Fe, once a week. Or about 230mg per the 160L.
I also had Fe DPTA 7% and used that a little during this period, but went with the Rexolin for all in one given the ratios were pretty ideal based on scientific literature. My original plan was to dilute the LCA stuff with the Fe DPTA to get a better ideal ratio, but ended up finding Rexolin APN in Aus on ebay.
So the 1st week I got some improvement again, but by about week 4 it is evident that the toxicity is creeping back in.
But as soon as I reduce the micros, the floaters do bad, but too much I get some toxicity symptoms too. So it seems the line between toxic and not enough is small and happens quick in the floaters at least.
I know for sure the good large poly is def doing better with less, the holes stop appearing in the newer leaves at the lower dose and the colour seems ok, maybe slightly yellow in new growth, but does go green eventually as it gets older.
The cory was my best plant, it is now a mere fraction of the size it was, 90% lost and still looking sick.
The water spangles have gone to crap within a week and a half of reducing the micros, but the rooted plants are still showing signs of toxicity. The spangles show all new growth to have square patches in a grid pattern that are white and some are tuning into holes. Older leaves are ok and the original plant looks great except a new leaf is forming with the same white squares.
I had square holes often in the frogbit, but I removed them as they drowned all the other floaters which nearly lost all my red root. The duckweed still looks ok and grows like mad regardless, I scoop it out twice a week, but new ones always look slightly yellow until they age and finally turn green. Not even a pale green or white, but actual yellowy green. So Fe?
I went down to 70mg going by Barr's suggestion weekly or every 2nd , 35-70mg equiv of of the Equilibrium ignoring Fe, and just looking at Mn and others, So this is what I suspect, that the micro mix isn't enough for Fe, but too much of the other traces, at least in my tank.
So when I increase the Fe as all in one micros, it seems the iron levels satisfy the floaters and they seem to deal with or even like the high micros, but the Fe is adequate for the rooted ones at low dose, but the other traces are still toxic.
So I have started from the weekend to bi-weekly dose Fe DTPA at 0.08 x2 and will up the dosing based on testing, and I have stopped the Rexolin all together for at least a bit until the other traces deplete.
So I wonder if anyone else had an experience like this. I was able to replicate it at least twice or thrice in the main tank. I made a small scale bowl setup with the Barr onyx/leonardite base to experiment with, all from scratch, I got the wisteria which I no longer have in the main tank as it never grew at all after using ferts. This started to take off and I thought yes! finally I solved it, added Rexolin, 2mg to 1.7L, 1st time ok, 2nd time still ok but maybe the leaves stopped growing, 3rd week, the plants went to crap, roots and all stopped growing. I did a 80% change on the bowl, Fe and macros only and I see they are pearling again (stopped when I added the Rexolin 3rd time) and I see new root buds forming again, the new roots from 3 weeks ago all stopped and look like they are going to rot off.
So for sure the micros are toxic, but at a far lower dose that I ever thought or read. So my question is, for a low tech tank that is also kinda cold water. What is a good dosage guideline for micros ignoring Fe, as it seems Fe is needed in larger amount regardless in my testing.
I have always suspected it's Mn that is causing the majority of the issues as I have dosed inorganic micros many months ago as separate chemicals before I could find any chelated ones. And I never had issues with similar higher amounts of Zinc or Cu, I didn't have Boron as that is banned it seems, I had Mn, but as SO4, so I suspect it was quickly unavailable as was in the Equilibrium.
The best results I ever had when I was dosing 2-4x Flourish, plus 40ml of Seasol (seaweed extract food for gardens sold everywhere in Aus)
And I think that the Flourish's super low traces was enough and not toxic, but the iron that came from the Seasol (0.16ppm per week) was working. But seasol makes your water super dark and the axolotls seemed to freak a bit, so I went the dry chemical route.
So again, I am gathering that Fe needs to stay at the more typical levels, but all other traces need to be super low in non co2. I have read a few other threaded on the net that suggest a similar thing, micros become toxic easily , but iron dosed separately is still a requirement, one thread a person with co2 had all the same symptoms but it was a combo of too much micros and not enough PO4. So I guess the micros look again to be my problem.
I just stated this routine on this hypothesis and will see how it goes. If this is indeed the case, then why are the ideal ratios of micros and Fe which is a micro are so far off in reality compared to scientific literature, and secondly, if this is a common issue which it seems it is, then why do micro mixes use Fe as the dosing proxy when all the other traces are the ones to be careful of and doubly so when they are so toxic so easily, where iron isn't really unless at magnitudes higher than normal.
Thanks in advance for any advice or ideas.
The title isn't the whole question, it's far more complicated the issues I am having but I think I have a fair idea of the right path, hopefully, I guess that's why I am here to ask if my hypothesis is in the ball park.
So anyway, my setup currently is a non co2 temperate low light tank with two pretty large axolotls. The tank is 122 x 35.5 x 50ish cm, so a non standard 4' and a fraction of an inch size. Yeah, I had to custom order a custom made tank to replace this one soon as it is damaged, 4th or 20th owner, who knows, I'd say it's from the 90s
The substrate unfortunately is just quartz play sand from the hardware store (Bunnings for fellow Aussies), long story but FB groups steered me in all the wrong directions).
I have all the stuff to setup the replacement tank in the new year using the Barr non co2 method, but for now I am learning all the ways I can break stuff on this one.
The plants are mainly hygros, Polysperma, Corymbosa, a single sword, two anubias, recently added microsorum to a drift wood piece, and two normal pond lillies.
There is some small amount of java moss too, but nothing signifcant.
I have floaters, heaps of duckweed, fair amount of red root, and surprise water spangles, only just starting to spread.
So here in Aus, ferts are all crap, impossible to get anything good. So many months ago I went the macro way of dry salts from a chemical shop and was also lucky enough to be able to get KNO3 which was silently banded here for a good few decades but now relaxed laws allows you to gt basic chemicals again.
Macros are a non issue.
KH2PO4 every two weeks and maintain about 2ppm
CaCl and MgSO4 for the GH upon WC, sometimes a top up after several weeks, just drops maybe 1 GH over that time.
KNO3, barely ever use it, bio-load is more than high enough. Just sometimes after a WC to bring the NO3 back to range as it can take about two weeks for it to naturally go high enough.
K2SO4 for K, just once upon WC, never really moves for months
Water parameters are:
160L total
18.5c
Ph 6.5
GH 7-8 at Ca to Mg of 2.5:1
KH 1.5
K, 30ppm
NO3 25ppm
PO4 2ppm
TDS 250-300 ppm normally
Fe try to dose up to 0.1 0.2ppm total, split bi-weekly atm. Normally always detectable in Fe test. Used to go as high as 0.4ppm but micro mix nuked the plants.
Light, Beamswork Vivio, low light type of thing, full spec., 10 hours.
WC, only after 2-3 months when the tank is full of mulum.
Micros I tried many, seachem ones were so weak that literally no change, even at like 4x the dose. No change what so ever. Iron test always showed zero iron despite dosing saying otherwise.
Tried the Equilibrium, kinda worked but needed way more than the Barr method and ended up with too much everything else, but no OD symptoms, just went to deficiency if I stopped dosing as much or as often, never got the deficiency sorted like I wanted. I think that needs the the substrate outlined in the method for this to work well, inert sand doesn't cooperate.
Purchased AquaForest Micro, all suppliers in Aus were not able to get it and my one I purchased got lost in the mail. So I ended up being given a refund. Still can't get that.
After looking for something unrelated I found LCA micro mix from LCA in QLD Aus, and yeah that's when the problems started but at the same time also helped my floaters finally grow.
I was dosing to about 0.2ppm of Fe that the proxy said. Eventually I found out that the ratios are way off and they had something 4-6x the Mn and Zinc and Cu over the iron.
So I thought, ok, that was my prob.
The problem was all my hygros stopped growing, got symptoms of severe K difference, Mn/Mg/Fe like symptoms, N symptoms, and all the old leaves fell off over a few days, some of the new leaves and the middle ones seemed to be ok but a bit holey. Nothing wanted to grow.
However, the floated actually took off but the frog bit seemed to fuss. Less micros, they got square holes in them, more micros, they corrected but all the other plants below start dying.
The red roots also showed better color and growth with more micros.
Interestingly, my macros went up and Fe levels stopped going down, so the toxicity blocked all uptake it seemed.
LCA micro mix link here, and yeah, not good ratios and dose suggested a crazy high too. I dosed half the dosing from get go and half a frequent, and even reduced it more when this was happening.

Trace Mix Premium Dry
LCA Trace Mix Premium Dry mix of 6 micro nutrient EDTA chelates with Magnesium (Mg) as 100% soluble micro-granule. Provides the necessary micronutrients required for lush healthy growth. Add 450 milligrams into 100L tank twice per week with 30-50% weekly water change.*Note* Amounts above are for...
So I bought some Rexolin, did a 90% WC, left it for 2 weeks and started again.
This time I dosed to 0.08ppm Fe, once a week. Or about 230mg per the 160L.
I also had Fe DPTA 7% and used that a little during this period, but went with the Rexolin for all in one given the ratios were pretty ideal based on scientific literature. My original plan was to dilute the LCA stuff with the Fe DPTA to get a better ideal ratio, but ended up finding Rexolin APN in Aus on ebay.
So the 1st week I got some improvement again, but by about week 4 it is evident that the toxicity is creeping back in.
But as soon as I reduce the micros, the floaters do bad, but too much I get some toxicity symptoms too. So it seems the line between toxic and not enough is small and happens quick in the floaters at least.
I know for sure the good large poly is def doing better with less, the holes stop appearing in the newer leaves at the lower dose and the colour seems ok, maybe slightly yellow in new growth, but does go green eventually as it gets older.
The cory was my best plant, it is now a mere fraction of the size it was, 90% lost and still looking sick.
The water spangles have gone to crap within a week and a half of reducing the micros, but the rooted plants are still showing signs of toxicity. The spangles show all new growth to have square patches in a grid pattern that are white and some are tuning into holes. Older leaves are ok and the original plant looks great except a new leaf is forming with the same white squares.
I had square holes often in the frogbit, but I removed them as they drowned all the other floaters which nearly lost all my red root. The duckweed still looks ok and grows like mad regardless, I scoop it out twice a week, but new ones always look slightly yellow until they age and finally turn green. Not even a pale green or white, but actual yellowy green. So Fe?
I went down to 70mg going by Barr's suggestion weekly or every 2nd , 35-70mg equiv of of the Equilibrium ignoring Fe, and just looking at Mn and others, So this is what I suspect, that the micro mix isn't enough for Fe, but too much of the other traces, at least in my tank.
So when I increase the Fe as all in one micros, it seems the iron levels satisfy the floaters and they seem to deal with or even like the high micros, but the Fe is adequate for the rooted ones at low dose, but the other traces are still toxic.
So I have started from the weekend to bi-weekly dose Fe DTPA at 0.08 x2 and will up the dosing based on testing, and I have stopped the Rexolin all together for at least a bit until the other traces deplete.
So I wonder if anyone else had an experience like this. I was able to replicate it at least twice or thrice in the main tank. I made a small scale bowl setup with the Barr onyx/leonardite base to experiment with, all from scratch, I got the wisteria which I no longer have in the main tank as it never grew at all after using ferts. This started to take off and I thought yes! finally I solved it, added Rexolin, 2mg to 1.7L, 1st time ok, 2nd time still ok but maybe the leaves stopped growing, 3rd week, the plants went to crap, roots and all stopped growing. I did a 80% change on the bowl, Fe and macros only and I see they are pearling again (stopped when I added the Rexolin 3rd time) and I see new root buds forming again, the new roots from 3 weeks ago all stopped and look like they are going to rot off.
So for sure the micros are toxic, but at a far lower dose that I ever thought or read. So my question is, for a low tech tank that is also kinda cold water. What is a good dosage guideline for micros ignoring Fe, as it seems Fe is needed in larger amount regardless in my testing.
I have always suspected it's Mn that is causing the majority of the issues as I have dosed inorganic micros many months ago as separate chemicals before I could find any chelated ones. And I never had issues with similar higher amounts of Zinc or Cu, I didn't have Boron as that is banned it seems, I had Mn, but as SO4, so I suspect it was quickly unavailable as was in the Equilibrium.
The best results I ever had when I was dosing 2-4x Flourish, plus 40ml of Seasol (seaweed extract food for gardens sold everywhere in Aus)
And I think that the Flourish's super low traces was enough and not toxic, but the iron that came from the Seasol (0.16ppm per week) was working. But seasol makes your water super dark and the axolotls seemed to freak a bit, so I went the dry chemical route.
So again, I am gathering that Fe needs to stay at the more typical levels, but all other traces need to be super low in non co2. I have read a few other threaded on the net that suggest a similar thing, micros become toxic easily , but iron dosed separately is still a requirement, one thread a person with co2 had all the same symptoms but it was a combo of too much micros and not enough PO4. So I guess the micros look again to be my problem.
I just stated this routine on this hypothesis and will see how it goes. If this is indeed the case, then why are the ideal ratios of micros and Fe which is a micro are so far off in reality compared to scientific literature, and secondly, if this is a common issue which it seems it is, then why do micro mixes use Fe as the dosing proxy when all the other traces are the ones to be careful of and doubly so when they are so toxic so easily, where iron isn't really unless at magnitudes higher than normal.
Thanks in advance for any advice or ideas.
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