# Progressive Flooding (after Dry Start Method)



## Zedan (3 Apr 2019)

Would it be effective to flood the tank slowly, over the course of a week, to allow the plants more time to adapt to submerged life.
This would better replicate the natural way in which plants at the water's edge experience changes in water level from emmerged to fully submerged.
In addition, I would expect the plants to continue making use of the atmospheric CO2 from leaves above the water.

For example. Generously spray the tank every day, raising the water level by <5mm each day until the water is above all the plants and then fill the tank as normal.

Thoughts?


----------



## Fiske (3 Apr 2019)

Initial thoughts: If it should give the plant time to acclimatise to submerged growth, it should take several weeks probably. In the interim period, you wouldn't be able to run the filter. Thus risking massive algae. Just my 0.02€.
I could be wrong.


----------



## zozo (3 Apr 2019)

Plant morphology and or even atonomy in aqautic form can be quite different.. There are some scientific papers listing the differences in the researched sp. I know these roam somewere around in this forum.

An example is the terrestrial grow form developes stomata, the aqautic form doesnt develop them. Also the outer skin layer of the leaf can be completely different. Most likely the majority of plants will need to transition completele into its new form, shedding all its terrestrial developed tissue.

Ths it depends a bit on the sp. and that is hard to say.

Take for example Anubias doesn't seem to need this transition, at least i yet didn't experience it and have quite a lot anubias growing.

Even other way around going from submersed to emersed.. As i experienced with several crypt sp. Going from the aqaurium to a little greenhous.
As long as humidity is high enough it seems the leaf transitions in both forms. Tho Sagittaria completely dies off and comes back with new growth from the rootsstock.

Maybe members can share their personal experiences if you give a list of plant species involved.


----------



## Zeus. (3 Apr 2019)

Zedan said:


> Generously spray the tank every day, raising the water level by <5mm each day until the water is above all the plants and then fill the tank as normal.



IMO -NO- reason is diffusion in water is 10,000 slower than in air so we need flowing water over the plants or they will suffer and die so either DSM or flood with good flow CO2 etc


----------



## X3NiTH (3 Apr 2019)

The way I would approach this would be to perform the inundation during the night cycle to get around the above issues. My reasoning for this would be that many tropical plants are inundated periodicaly as a consequence of overnight rains. Plant tissues should have a decent amount of O₂ stored from the daylight period and if they are flooded with oxygen rich water in the dark while respirating then CO₂ content is a non issue, if the plants are going to adapt to being submerged then this is probably the best time for them to do so (epiphytes get to uptake nutrients from the water column that they can use the next day cycle if the substrate they are attached to is nutrient poor). 

I would fully immerse the plants over night beginning with a short period of flooding then draining say over about an hour (arbitrary amount, this could be a shorter or longer period) and then extend this period of flooding over time so that it eventually starts cutting into the daylight cycle (the water would have to be CO₂ rich at this point). Hopefully over time the plants will have adapted to being inundated for the majority of the day cycle.


----------



## Fiske (3 Apr 2019)

That's some sound advice @X3NiTH
That might be a way to do it. It reminds me of a post I can't find anymore about Aquasabi doing the same in their nursery/warehouse/whatever. There's also this thread https://www.ukaps.org/forum/threads/hydroponic-culture.52317/#post-515381

That's quite a system to set up though, still not sure what the benefit would be really.


----------



## Zeus. (3 Apr 2019)

X3NiTH said:


> I would fully immerse the plants over night beginning with a short period of flooding then draining say over about an hour (arbitrary amount, this could be a shorter or longer period) and then extend this period of flooding over time so that it eventually starts cutting into the daylight cycle (the water would have to be CO₂ rich at this point). Hopefully over time the plants will have adapted to being inundated for the majority of the day cycle.



Sounds like a lot of hard work, Plus when the flood starts cutting into the daylight period the Plants 30ppm [CO2] in water (if CO2 injection is used) then jumps to 400ppm [CO2] in air plus great diffusion rates!! so the [CO2] is up and down and the quote @ceg4048

[QUOTE="ceg4048, ]we know that when the plant senses that high concentrations of CO2 is available, it responds by reducing the production of expensive Rubisco. When it senses a lower CO2 concentration it must increase Rubisco production, however because this protein is so complicated and heavy, the increased production requires 2-3 weeks in order to change the density in the leaf to match the new gas concentration level. So it is much easier to reduce production than it is to increase production. When increasing gas injection therefore, it hardly takes any time to see an improvement in health. When lowering the concentration, the plant will suffer because it must now ramp up Rubisco production to account for the loss of CO2 availability.[/QUOTE]

Sounds like the plants are going to using a lot of energy trying to adjust to variable [CO2] all the time. Which is why Clive goes on about getting a stable [CO2] in out CO2 injected tanks for the main photoperiod is key to success when injecting CO2. With the water levels changing all the time cant see it benefiting the plants in the long term, if anything there more likely to run out of energy


----------



## X3NiTH (4 Apr 2019)

Zeus. said:


> Sounds like a lot of hard work, Plus when the flood starts cutting into the daylight period the Plants 30ppm [CO2] in water (if CO2 injection is used) then jumps to 400ppm [CO2] in air plus great diffusion rates!! so the [CO2] is up and down and the quote @ceg4048



Certainly it would take a decent amount of planning to accomplish and some of the hard work could be eased with a little bit of automation. The dry start method is so hit or miss though and it can fail for many reasons, when things start to go wrong the end result is generally flooding the tank (earlier than intended) and the plants have no option but to adapt or die, the later outcome more likely if the plants are already under stress (Mold, it's the no1 reason to flood the tank early).

There's going to be a lot of variation in how different plant species will cope with inundation. Assuming a tropical climate for the dry start then doing it like nature would be that when wet seasons approach rain usually starts falling earlier before nightfall and with increasing intensity and durarion over time, riparian plants in this environment would have to go through ever increasing periods of inundation or in the extreme being immersed outright for periods of time. The aim is to give plants an advantageous start as possible and when I talk about introducing inundation into the day cycle I should have mentioned that I would start in the dark early evening when the plants are respirating then work my way progressively earlier over time so that when it gets permanently flooded it's mid to late afternoon in the light cycle, also when I say CO₂ rich water again I should have specified that it doesn't have to be 30ppm, for no animals are involved at this stage and you can enrich the inundation water with as much CO₂ as you can cram into it and then slowly dial that back down over time to 30ppm before the introduction of animals. 

The period of inundation can also be used to tend to problems arising from the dry start method itself such as Mold formation by treating affected plants with H₂O₂ directly before flooding (flooding after dosing reduces the risk of the peroxide harming the plants) or adding other preventative anti-whatever to the inundation water. It could also be used where there is an active high CEC substrate to increase the chance of it forming an equilibrium with the water over time, so no surprises on flooding day, whether it takes up or gives to the water column will be dependent on the mineral content of the water.

I have no idea if these suggestions would be an improvement over the current method as I haven't tested this approach myself, it's certainly a more complex extension to Ebb and Flow. Inevitably when a Dry Start thread comes up it always gets the gears working, and the extra gear added tonight is 'how good are aquatic plants in the wild at adapting to inundation periods with rising atmospheric CO₂ in an unchanging atmosphere/water equilibrium gradient'.


----------



## Zeus. (4 Apr 2019)

Think what happens in nature is what the plants have had to overcome to survive and flourish and may not be the best approach to success when going from DSM to flooded.



X3NiTH said:


> Inevitably when a Dry Start thread comes up it always gets the gears working, and the extra gear added tonight is 'how good are aquatic plants in the wild at adapting to inundation periods



IDD  always good the think things though and chat/share our thoughts/opinions/ideas 

I must admit your posts @X3NiTH do contain some deep thinking


----------



## Tim Harrison (4 Apr 2019)

I think that you'd be better off just flooding completely in one go, and making sure your CO2 is implemented as efficiently and effectively as soon as possible.
The danger flooding slowly over a period of time is that you might be condemning your plants to a slow death by suffocation, and therefore encouraging algae instead.
Most of the plants we grow in our tanks are tropical and can experience rapid inundation via seasonal flash floods, so a slow immersion period is not necessarily natural.


----------



## zozo (4 Apr 2019)

My 5 cents on it, stays with which plant sp. are involved..  Mainly epiphytes don't realy go through this transition cycle as stem plants would do.
If you search the forum there are some threads to be found where respected well experienced members say, keep new plants floating for a while, since top layer of the water surface contains more co². it helps them to get used to the newer flooded conditions.. Sorry i'm a realy bad bookmarker with alzheimer and dyslexia light, but i know these threads excist, just do not remeber where they are and which plant sp. were involved..

Anyway, these threads/remarks do not excist for nothing.. The point is make an inventory of which plants sp. are in majority by preferences.

The winner takes it all..  Get to know your plants..

By experience i know that Bolbitis, Anubias, Buce and mosses do not tend to melt away so drasticaly when placed suddenly submersed. If they do it depends on depth. flow and light or co² availability (depth).. But mosses are a completely different issue with loads of different forms.


----------



## zozo (4 Apr 2019)

Another example i almost forgot (or didn't i? dunno anymore).. I'm growing several crypt sp. emersed ans well as submersed. I do not see much difference, in both forms that are relatively anatomicaly the very same plant.

Compare this for example to several rotala sp. and you'll notice a very different anatomical difference between both forms. Now i have to guess but i ten dto beleive if there are noticable anatomical differences in grow form, there likely are major morphological differences as well.

If there doesn't change much in this in a plant sp. My best guess is the more addaptable they are to grow in either this or that.. 

Plant is not something universal.. Probaly the most versatile lifeform on this planet.


----------

