Rotala Kill Tank

burr740

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Still I have to wonder how "lean" the water column actually is. Seems like there'd have to be a lot of nutrients leeching into it?

Which doesnt change the fact that plants seem to love having tons at the roots, just wondering if we can actually call it a lean water column...
 
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fablau

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Still I have to wonder how "lean" the water column actually is. Seems like there'd have to be a lot of nutrients leeching into it?

Which doesnt change the fact that plants seem to love having tons at the roots, just wondering if we can actually call it a lean water column...

Good point Joe. I am really surprised it is working so well with so much light. It’s got to have some stuff leaching in the column... Vin, your thoughts?
 
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Pikez

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Good point Joe. I am really surprised it is working so well with so much light. It’s got to have some stuff leaching in the column... Vin, your thoughts?

I am certain there is SOME leaching going on. But since I don't disturb the substrate much or uproot stems, the leaching is probably minimal.

Two reasons why I think leaching is minimal:
  1. Little to no algae given the amount of light.
  2. The Water Lettuce that were 8" diameter a few weeks ago are now 2 to 3" diameter at the most. So the water column is nutrient limited. That's the beauty of having floating plants - they are not light or CO2 limited. Floating plants are really good indicators.
 

X3NiTH

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Measuring the conductivity between water changes would give some idea as to how much is being leached into or reduced from the water column. That's the only thing I would test for.
 
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fablau

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I am certain there is SOME leaching going on. But since I don't disturb the substrate much or uproot stems, the leaching is probably minimal.

Two reasons why I think leaching is minimal:
  1. Little to no algae given the amount of light.
  2. The Water Lettuce that were 8" diameter a few weeks ago are now 2 to 3" diameter at the most. So the water column is nutrient limited. That's the beauty of having floating plants - they are not light or CO2 limited. Floating plants are really good indicators.

Makes sense the second reason Vin, but the first one is not clear to me... it is right because you have high light that your plants would need more ferts from the water column than without. Isn’t the rule “the more light, the more ferts must be given”?
 

Pikez

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Makes sense the second reason Vin, but the first one is not clear to me... it is right because you have high light that your plants would need more ferts from the water column than without. Isn’t the rule “the more light, the more ferts must be given”?

Reason #1 was...if there is ammonia leaching into the water column, I would not be able to go this long without needing any glass cleaning. I do water changes every 15 days now and still, no need to clean glass. If there was uncontrolled leaching into the water column from the 1 lb of Oscmocote, I would imagine there would be some imbalance of some sort. So, at the very least I'd expect some GDA from the N being leached into the water.

Unbalanced tank + high N in the water = GDA
Unbalanced tank + no N in the water = no GDA (but other kinds of algae)

As for high light, yes, nutrient demand will be higher. But there is an excess of nutrient in the substrate. Water column can be completely devoid and plants will still be fine.
 

fablau

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Reason #1 was...if there is ammonia leaching into the water column, I would not be able to go this long without needing any glass cleaning. I do water changes every 15 days now and still, no need to clean glass. If there was uncontrolled leaching into the water column from the 1 lb of Oscmocote, I would imagine there would be some imbalance of some sort. So, at the very least I'd expect some GDA from the N being leached into the water.

Unbalanced tank + high N in the water = GDA
Unbalanced tank + no N in the water = no GDA (but other kinds of algae)

As for high light, yes, nutrient demand will be higher. But there is an excess of nutrient in the substrate. Water column can be completely devoid and plants will still be fine.

Makes sense now... thanks :)
 

Pikez

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Here's the latest on the 1-pound-Osmocote Kill Tank

Plants that have 'struck gold' deep in the substrate look robust, big, rich, and healthy.

Here's the tank during one of its bimonthly water changes. Not much algae. Ignore the back wall - it has not been cleaned in 2 years. Overall, the growth is dense with little or no algae. Biomass is growing exponentially and it will have to be managed in the next week. Water Lettuce remain small at 1-2" diameter, compared to palm-sized a month or so ago. This tells me that the water is fairly lean.




Here's Cuphea anagalloidea, a classic Lythraceae. A really pretty plant that can be a pain in the ass for a lot of people, including me, if exclusively water-column fed. It is a weed when grown emerged. It does well in fresh (non-depleted) Aquasoil. I have grown it half a dozen different ways to see how it grows best. It has NEVER grown with as much vigor desire to take over the world.

When Cuphea is exclusively water-column fed, it branches excessively, has very short internodes, crinkled new leaves, and pitted older leaves. Feeding it from both ends significantly minimizes these symptoms. But feeding it exclusively through the roots eliminates these issues.



Here is Cuphea in my big Aquasoil tank (old, depleted soil, so I have to water column feed). Notice the rich color from the Aquasoil. Also notice the new leaf distortion and pitting in older leaves.



Here's Rotala tulunadensis. Another pretty but pain-in-the-ass plant. It's difficult to get leaf shape just right. Stem melts are also common when leaf-fed.



Ludwigia senegalensis looking particularly rich and juicy with wine red leaves.



 

rajkm

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That Tulu looks great. I got rid of mine since it only stayed green and some white on top and looked uninteresting, but now, looking at your pic at think I didn’t do it justice.
 

fablau

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Fantastic update Vin! It's amazing how well Cuphea is growing with just root feeding, in my small 20gl farm tank with EI and high Co2 doesn't grow at all. I'll try to feed it through the roots with some osmocote and see if it makes any difference, as you suggested. I am curious to know if Joe (Burr) can grow that plant in his tank with just water column dosing.

Also, one question: do you use nose-bleeding Co2 in this tank as well?

Thanks again :)
 

EvanBriggs

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what is your parameters at this point?

Im noticing that low Fe helps in my tank. Increased, leaves stunted, then i decreased even more than it was .2 fe to .1. plants are thriving now.
 

Pikez

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That Tulu looks great. I got rid of mine since it only stayed green and some white on top and looked uninteresting, but now, looking at your pic at think I didn’t do it justice.

Bite your tongue, Raj! It's one of the rarest Rotalas in the world. I hope you gave it to someone else instead of chucking it.

In your defense, this is a hard plant to grow with perfect leaves. It is, however, just as hard to kill! It grows in most of my tanks, while looking like crap for the most part. But if you root-feed it with fresh aquasoil and/or Osmocote, it will look gorgeous. The first people I gave this plant to (Cavan Allen and Kris Weinhold) are growing it well. I know Cavan's look great - he just sent me a video of it. He grows it with light water-column and MTS-capped substrate. Cavan's Tulu actually look better than mine from top to bottom. We haven't figure out the rapid-on and rapid-off white leaves at the top are really iron-related. If it really is iron-related, this takes the crown as the best iron indicator ever from Limno mini aromatica and a couple of others.

An even rarer, picker plant that is virtually indistinguishable (to me anyway) is Rotala sahyadrica. I had it for a while. Tough. I don't know if it will ever come back into the hobby. Even if it does, it will have to remain in the hands of master green-thumb growers who also give a $h1T rare species discovery.
 

Pikez

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Fantastic update Vin! It's amazing how well Cuphea is growing with just root feeding, in my small 20gl farm tank with EI and high Co2 doesn't grow at all. I'll try to feed it through the roots with some osmocote and see if it makes any difference, as you suggested. I am curious to know if Joe (Burr) can grow that plant in his tank with just water column dosing.

Also, one question: do you use nose-bleeding Co2 in this tank as well?

Thanks again :)

Yes, CO2 is high. My probe is busted, so I am not sure what the pH drop is, but it's probably between 1 to 1.4 drop. Frankly, you don't need to be anywhere near 1.4 drop.

Burr generally side-steps Lythraceae other than the Mac green, Mac Variegated and wallichii to some degree. I don't remember if I've shipped him Cuphea anagalloidea. May have. I'll have to send him some.

If I were to pick a way to stunt and twist this plant, this is what I'd do: very soft water, inert substrate, full EI, and spiky CO2.

On the flip side, if I wanted to maximize my changes of a healthy leaf growth, I'd so this: medium to hard water, rich substrate with a source of ammonia-N, and little or no water column dosing. If I wanted perfect leaves and brick red color, I'd grow it in fresh aquasoil with very light water column feeding. Color is ALWAYS better in Aquasoil, regardless of how old and depleted the soil is, even compared to the current Osmocote tank.

Fresh aquasoil + moderate water column dosing will work too. But as the Aquasoil gets depleted and you become increasingly reliant on water column, the top leaves will begin to curl and stunt.

If you have really old Aquasoil, the best thing you can do it starve it and lower the light proportionally to like 25 umols.

I feel like I've cracked this nut.
 
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Pikez

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what is your parameters at this point?

Im noticing that low Fe helps in my tank. Increased, leaves stunted, then i decreased even more than it was .2 fe to .1. plants are thriving now.

Hey Evan,

Water is hard, alkaline. KH about 7. GH is probably about 8 or 10...havent measured in a while.
CO2 is high. Right now, I have disconnected the reactor an am bubbling CO2 straight into a powerhead, which breaks up bubbles into a fine mist. Probably not the most efficient way to dissolve CO2, but it gets me to acceptable pH drop quickly. And for those who believe that actually physical misting of plants with fine CO2 bubbles is critical, well, the plants have that too.
Light is two Finnex LED strips with about 80-100 umols at the substrate.
Filtration is Fluval canister.
Water changes in the Osmocote tank is 90% every two weeks.
No fish.

Nothing special really. Just proper maintenance that most of us know we ought to do. If you're new to the hobby, I'd still focus on mastering CO2 and accept that lots of maintenance is crucial.

I haven't looked at the tank is a few days, but if I ignore it any more, biomass will get out of control as everything is growing really well and fast.
 

Phishless

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I got rid of mine
:(

I hope you gave it to someone else instead of chucking it.
o_O

We haven't figure out the rapid-on and rapid-off white leaves at the top are really iron-related.
FWIW I maintain .4ppm of Fe in the water column @ all times, not sure what is delivered from the capped soil.

Pic of sahyadrica @ the bottom, tulu is a few stems behind with darker tops.
5fac2ebe49acab51ba4c40dcf54503bd.jpg
 

burr740

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Vin do you have any AR variegated in the kill tank? Curious how flat the leaf edges get

Burr generally side-steps Lythraceae other than the Mac green, Mac Variegated and wallichii to some degree. I don't remember if I've shipped him Cuphea anagalloidea. May have. I'll have to send him some.

Macrandas, wallichii, Didiplis all do fine. Sunsets do great about 80% of the time. They'll grow wonderful for 6 months and then die all of a sudden.

Ammanias generally grow but look like shit. Currently have some crassicaulis doing...so so

All of the above is with high ferts, high co2 and high light. Its the same basic result in both sand and aquasoil. Sand tanks have a little O+

I've tried briefly a couple times low-dosing the Aquasoil tank but other stuff dont like it, and is quick to let me know. So I havent explored that option enough to see what would happen
 
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burr740

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DSC01329.jpg

Spreadsheet.jpg


Since the spreadsheet a few weeks ago he's raised NO3 and K by 5 ppm per week, PO4 currently 3. Fe is Seachem iron.