Anyone want to study refugium plants with me?

[GuppyBreeder180604]

One quick question from an ignorant bystander: how would you match the ideal water parameters for all these plants if you are going with a cichlid tank?

African, North american or south american?

 

[OnlyGenusCaps]

One quick question from an ignorant bystander: how would you match the ideal water parameters for all these plants if you are going with a cichlid tank?

For my part, I'm not. According to the papers I have read, the nutrient uptake capacity of Salvinia is not strongly pH dependent. I've not seen it tested for resistance to hardness specifically, but but higher pH is often associated with harder water (I know, I know, not invariably). This is part of why I am focused on a single species for the moment. I don't need to worry about factors that promote long-term coexistence, I don't have to worry about competition, nor about inhibition.

If I go the route of examining a secondary submerged plant, I'd likely go with one that can effectively make use of bicarbonates as a carbon source from the hard water in an African cichlid tank. Your hornwort suggestion comes to mind in that regard. However, there are a number of practical reasons I keyed in on floaters:

1. they tend to spread by making subsequent dividable units
2. they are easy to harvest (see above)
3. they have access to atmospheric CO2
4. if harvested regularly they don't tend to leave loads of detritus (this would be a concern with things like hornwort)
5. with no water column above the leaves, they get the full intensity of any light provided (can reduce battling diffusion and the inverse square law)

This is why I thought floaters were worth exploring for this purpose. To be sure, there are potential down sides too (e.g. producing biomass essentially in a single plane vs through a volume, pest control on emerged components, etc.). There might be a boost one could get from submerged plants, it's true. But as a start, floaters seemed reasonable. It's kind of the laziest route if it works out.

 

[eatyourpeas]

Mmm... How much surface are you providing? I still think Hornwort should not be dismissed as it can take advantage of the water volume without depending on just the surface area. Very easy to discard too, just remove the older stems.

 

[GuppyBreeder180604]

Mmm... How much surface are you providing? I still think Hornwort should not be dismissed as it can take advantage of the water volume without depending on just the surface area. Very easy to discard too, just remove the older stems.

The problem with hornwort is that it tends to shed it's leaves and that makes a bigger bioload than the one it consumed and it creates it on a shorter amount of time.

 

[eatyourpeas]

A very valid point.

 

[GuppyBreeder180604]

Why don't You also make my experiment?
If You read it you'll see that it doesn't have water parameters (Ph, Gh, Kh) because You are suposed to use the water with the parameters of your fishtank (in your case an alkaline hard water) to find the Best plants for YOUR specific situation, since the Best sump plants for a rio Negro biotope Will be different from the ones for a lake victoria biotope.

 

[OnlyGenusCaps]

Mmm... How much surface are you providing? I still think Hornwort should not be dismissed as it can take advantage of the water volume without depending on just the surface area. Very easy to discard too, just remove the older stems.

Your point about surface vs water column plants is well taken. To my mind, the core of what makes a good refugium plant can be broken down to two attributes: 1. how much surplus N (preferably from nitrate) can be exported per unit time, and 2. how low can it bring the nitrates down in the water volume.

The second bit is more straight forward. It's going to be a physiological attribute of a species that governs how low a concentration it can still find and obtain nitrate, assuming there is enough of it based on its uptake rate given the input rate. This second phrase alludes to the more complex first attribute.

The first attribute, the amount of nitrate you can pull out as plant matter, is more complex. It is based on the biomass production per unit time, along with the N content of that biomass, and the preference the species has for nitrate (vs say ammonium which vascular plants typically like much more). Your questions, I believe, deals with whether or not a surface growing will be able to out produce a submerged plant which can take full advantage of the water volume. I'm certain this can be figured out via a literature search. Finding studies that looked at biomass production, well really relative growth rate, would be the starting place. I fully admit, I have not done this. I have worked on the assumption that access to atmospheric CO2 reduces a limitation that would allow more growth. Plants like Hydrilla suggest that this may not necessarily be true (though I am not suggesting growing Hydrilla in violation of any laws that apply to anyone reading this).
This is all my round about way of saying that your suggestion bears some examining. I appreciate the thought with which you have replied to all of my posts here. Thanks!

 

[eatyourpeas]

This is a fun project. Lost of variables to juggle!

 

[OnlyGenusCaps]

Thanks. ATM it is literature research. Not that I mind reading science papers.

 

[eatyourpeas]

Better than perovskites

 

[OnlyGenusCaps]

There is nothing wrong with ABX3.

 

[eatyourpeas]

Absolutely not!

 

[eatyourpeas]

As I find it safe to assume you have already read most everything under the sun with regards to this subject, may I ask why you did not consider water lettuce a runner up?

I know I did not bring it up because I am fairly new to the hobby, but it seems less menacing than Salvinia molesta and perhaps a likely candidate.

Back to my bedtime rotifers...

 

[GuppyBreeder180604]

As I find it safe to assume you have already read most everything under the sun with regards to this subject, may I ask why you did not consider water lettuce a runner up?

I know I did not bring it up because I am fairly new to the hobby, but it seems less menacing than Salvinia molesta and perhaps a likely candidate.

Back to my bedtime rotifers...

I proposed water lettuce since it is an amazing nutrient eater but it can be as invasive and quick to breed as Salvinia if not more in some cases, still a worthy opponent in this battle for the best sump plants

 

[eatyourpeas]

Let the battle begin! Yes, they are both a pain in their invasive nature, and I wish I could see how you envision this tank/sump combination. Do you have a size in mind yet?