This update is connected to my travels as described on Post [HASHTAG]#1090[/HASHTAG] in the Dutch scape journal:
http://www.barrreport.com/forum/barr...quasoil/page73
I was basically gone for most of December. Gone for almost 2 weeks at first to the Amazon. No dosing at all during that time - wife was supposed to dose, but that didn't happen. Back home for 2 days. Did a trim, 90% water change and dosed macros and micros once in-between trips and was gone again for over a week. Again, there was no dosing during the second trip. No one was going to be home during the second trip, so I turned off one of the Planted+ strips.
The Kill Tank is fish-less and has an inert substrate. The ONLY nutrients are what I add to the system and from decomposing leaves. I do a good job removing old and floating leaves, so there is very little nutrient contribution from decomposition.
In a nutshell, the tank went a month with just 2 dosings. Macro dosing is moderate but not generous. Micros levels are very low. Given how low the micros are and given just 2 dosing of it, the tank did really well.
The tank did not look nutrient deficient after the first trip.
Ammannia pedicellata after being gone for two weeks:
However, at the end of the month, the tank looked like it was completely nitrogen deficient. Yet, there was no BGA or much of any other algae. The water was crystal clear.
The following plants were severely nitrogen deficient:
- Ludwigia Pantanal
- Rotala macrandra and rotundifolia (all forms)
- Rotala Red Cross (this plant suffered a lot)
A. pedicellata did OK. A. capitellata was showing signs of hunger. Rotala Sunset was unimpressive but ZERO melt or droop in the Kill Tank. (!!!)
Rotala Enie was not good. It may have suffered from nutrient limitation.
Many plants did REALLY well. Most notable is Rotala wallichii, the plant that was behind the creation of this Kill Tank concept. Frankly, I was amazed at how beautiful the wallichii leaves were. Near perfect. The color was a light rose and not bright red as they are in Tom's tank.
Bot the best picture (below), but it shows you the clean, unencumbered growth in Rotala wallichii after a month of near-starvation. I took this picture right after I returned home. It's been about 5-6 days now and the wallichii looks even better. The plant in the back in Hyptis lorentziana, another apparently hunger-tolerant plant. Hyptis is a good alternative to Acmella repens. Similar growth patters but with pinkish purple new leaves.
Other plants that did really well during the lean month:
- Ammannia gracilis
- A. senegalensis
- Hygro pinnatifida
- Floscopa scandens
- Proserpinaca palustris
- Cuphea anagalloidea
- Lagenandra toxicaria (?) green
- Rotala Mini Type 1 Pearl
- Ludwigia Red Diamond
- Ludwigia sphaerocarpa
- Erios Feather duster and breviscapum.
- AR Variegated
As you can see, I've stuck in one or two stems of odd plants to test their will to survive. L. sphaerocarpa is supposed to be a nutrient hog, but it was in decent shape after a month.
AR Variegated stems that I'd somewhat discarded after their leaves got too wrinkled and twisted in the Dutch tank got completely 'fixed' in the month during starvation. This plant is more challenging than AR Mini and FAR MORE challenging than regular AR to keep flat, straight healthy leaves. AR Variegated looks great in this tank.
I know Burr grows AR Variegated in his inert substrate, hard-water, very low trace tank without any issues. So I'm not surprised that it did well in the Kill Tank.
Frankly, at this point, the Dutch tank seems more like a test of a plant's will to survive.
I've added Erio setaceum Type 3 and two stems of Rotala mac Variegated to the Kill Tank to see if they do better here than in the Dutch. Both were pretty stunted in the Dutch tank after my return. I'm now growing both species in both tanks to see how they respond to being nursed back to health.
Rotala sp. Enie below (a wallichi type) did not do as well as real wallichii when ignored for a month. It appears this plant is difficult but in different ways than regular wallichii.
Cuphea anagalloidea (below) did fairly well.
So what did we learn, boys and girl?
Most of these plants are hardier than we believe they are, assuming adequate CO2 and light are present. My Dutch tank, it appears, is where I kill my plants with kindness. The Dutch tank is more of a 'killer' than the Kill Tank.
Nothing dies in the Kill Tank. Dang!
Given the improvement in appearance in wallichii during the month, when light and CO2 remained stable, the only conclusion I can make is that the plant is not just super tolerant of low nutrient levels, but may even thrive in it. We know that it does well in high-nutrient tanks like Tom's. We also know that it does well in low-tech tanks with soil, and low light.
This begs the questions:
- Could the Burr Method, which this tank is modeled after, do well with lower macros? I'd say no, given a fish-less tank. It may be OK if I added fish.
- Could the Burr Method, do well with EVEN LOWER traces? I'd say yes. I used to think that the Burr Method used shockingly low trace levels (it is about 5% or 1/20th of standard EI levels in traces). But given the majority of plants did really well with just two dosing in a month and the other plants ran out of nitrates (and not traces), I'm thinking these plants could do well with even lower traces.
I've been doing this for about 3 months with 1 month at the end of unintended starvation. Oops! Think that counts as a variable in the test. Oh well.
So what next? I used to think that, may be, the next phase of the Kill Tank should be a lower macro + same micro variation. But that's not looking very appealing at the moment. I want to explore keeping the macros generous and lowering the traces even more.
If I keep the macros the same (NPK at 6-0.75-6 every other day) and lower the traces by 50%, my hypothesis is that some plants will become eventually trace limited. I want to find out which ones will suffer and how long it'll take them reach breaking point.
Traces will be 0.0075 ppm Fe from CSM+B; 0.01 ppm Fe from Fe DTPA (Total Fe = 0.0175 ppm) every other day.
Is anyone even CLOSE to adding 0.0075 ppm Fe as CSM+B every other day? Worth finding out. I know that 0.0075 ppm Fe CSM+B seems ridiculous, but the tank went an ENTIRE MONTH with just 0.03 ppm Fe CSM+B. And look how nice the wallichii looks!
As much as I want to dismiss these observations, the numbers and the healthy wallichii are staring me in the face. I cannot ignore that.
But I see a few issues on the horizon:
- My Colombia exporter is getting ready to ship me the fish that I caught. I may need to put some of them in the Kill Tank.
- There may be some remodeling of the garage/fish room as I'm still considering expanding by adding a few 8-foot tanks.
- I have two international trips coming up in late jan and early feb. So dosing will be erratic for 2-3 weeks.