Inefficient Planted Tanks?

[MOA]

Hello,



I have been collecting data from aquarists for a week or two now with regard to the basic specifications of their aquariums. The principal result that I uncovered was a seeming contradiction to conventional wisdom with regard to planted aquariums:



Planted Tanks: Contradictory Data (MOA's: How Many Fish?, Stocking Freshwater Aquariums)



Read it, please, and then post what you think. Thanks for your contributions.



MOA

 

[lauraf]

Hmm, interesting. Thanks for sharing. I didn't think plants were the only way to have a happy tank and healthy fish; but I did assume that they helped.
I am finding that plant husbandry is maybe even more challenging is some ways than fishraising, but I enjoy it, and also appreciate the aesthetics.
And, MOA, given that you were looking for twenty submissions in total from MFT, was that your full data sample? Did you take into account the inherent reporting errors from the fishkeepers themselves? I.e., maybe there is a whole psychological profile to aquarists who keep plants vs those who don't, and likewise how they would rate themselves in terms of experience, and how accurately they would measure both biomass and degree of 'plantedness'?

 

[MOA]

lauraf,

You bring up an excellent point that I should have mentioned: this data is from the aquarist's viewpoint. That is, I am trying to redo some of my old equations and my equations have to be run independent of my censorship. Consequently, all my equations have to work off of the "average" response of the aquarist and that is the only data that means anything to me: What is the effect of the facts as mediated by the aquarist? very good point to bring up.

Also, I did not reach even my hoped data sample and that is why my article became a planted versus non-planted discussion. I also hoped that the premature release of this data would spark a debate that would eventually make it easier to get more people to respond to my research projects (methods to the madness). It should be understood that my work is incomplete and that, with more samples, the trend may be reversed.

I simply found it odd that the efficiency of non-planted tanks was roughly double the efficiency of all the other classes of tanks. I think that these results will make all aquarists think about efficiency in a new way.

Thanks,
MOA

 

[OrangeCones]

From my own experience raising fry, my water quality is far better in a planted vs. a bare tank. I can put the same number of fry in identical 10 gallon aquariums, one with live floating plants, the other with fake floating plants (to offer them a sense of security).

In two days, I need to do a 50% water change on the fake plant tank, while the real plant tank can go a week or more.

I can 'overstock' a planted tank with no problems. I don't keep non-planted tanks anymore, but I was never able to maintain the fish occupants in the numbers I have now, in a plant-free tank, without a tremendous amount of work (water changes to remove nitrates) on my part.

The key, I believe, on whether a plant is going to take in enough nitrogen waste (they take in ammonia first choice, then nitrite, then nitrate), is if the plant is actually in the right environment to thrive.

Many (but not all) newer fish hobbyists have inadaquate lighting to allow for fast growth (and more nitrogen uptake). A 15 watt bulb over a 29 gallon tank (what my 29 gallon tank came with when bought as a kit) would barely keep any plant alive. At 1/2 watt per gallon and a tall tank, light is hard pressed to get to the gravel to do any good.

It now has 2x55watts with an vastly improved reflector. I can keep medium and high light plants in there now (although I must inject CO2 and add fertilizers ~including EXTRA nitrogen~ to run both lights, or risk algae taking advantage of the extra light). I must trim the stem plants weekly, or 'top' them, removing the bottom half and replanting just the tops. Everytime I take a portion of the plant out, I'm removing nitrogen without having to do a water change. The cut plant now goes into overdrive to repair itself and/or put out new roots, so takes in more nitrogen.

Another factor is the plants chosen for the aquarium. My own LFS do not sell many aquatic plants. A bamboo plant, or the dreaded 'mondo grass' is most commonly seen. Those plants cannot survive underwater long-term, let alone 'thrive.' As they decay, they add to the nitrogen waste of the tank environment.

Just my 2cents.
OC

 

[MOA]

Valid Points,

OrangeCones, your post illustrates something that is very important to the study of planted tanks as a whole: A planted tank is not the same as a "properly" planted tank. I do not think that anyone could refute that properly planted tanks are far more efficient than their non-planted counterparts. What alarms me, however, is that many aquarists assume that adding plants will help even though their plants will only add waste if the lighting levels are insufficient, etc. In my data collection, the only distinction was essentially planted/non-planted. This means tha, of the aquarists sampled, their systems are generally not in the "properly" planted category.

MOA

 

[Newman]

ok maybe I needed to submit the data for more than just one of my tanks..
It is very curious to see how a plantless tank is more efficient. though that is likely due to very good tank upkeeping

 

[lauraf]

What alarms me, however, is that many aquarists assume that adding plants will help even though their plants will only add waste if the lighting levels are insufficient, etc.

Ah, that gets to the crux of the matter, and now I understand what was driving your interest. I probably still fall into that category, i.e., any plant is better than no plant
Really good point! Knowing this, maybe you could fine tune the survey to ask really specific details about how the tank is planted, e.g., types of plants, how well they grow, etc., to better determine whether the subject's tank is 'properly' planted, or just planted.

 

[blue_ram]

Hello,



I have been collecting data from aquarists for a week or two now with regard to the basic specifications of their aquariums. The principal result that I uncovered was a seeming contradiction to conventional wisdom with regard to planted aquariums:



Planted Tanks: Contradictory Data (MOA's: How Many Fish?, Stocking Freshwater Aquariums)



Read it, please, and then post what you think. Thanks for your contributions.



MOA

Interesting, but flies in the face of established well known facts on photosynthesis which indicates flawed data or flawed controls.

For such a study to have validity, you must have some sort of controls.

1. Is lighting the same accross all tank types?
2. Is water chemistry the same?
3. Fertilization?
4. C02?
5. Plant species.
6.. Filtration

You can go even further by adding in such variables as spectrum and CRI of bulbs.

Also, many popular aquarium plants are not true aquatic plants and will simply rot in the tank increasing nitrogen.