The levers of a balanced low energy tank

Big G

Member
Joined
20 Apr 2020
Messages
80
Location
London&Thanet
Evening all,

Just want to make sure I have understood a few concepts here correctly.

If I have understood what I have read then we have essentially three main levers we can adjust to bring our tanks to what we call balanced?
These are;

Light
Fertilisation
co2

....arguably variations within those regimes offer ‘trim control’ - for example flow.

If I take the above to reasonably uncontroversial then could we not say the following;

In a low tech/low energy setup we have no direct control over our co2 beyond attempting to ensuring optimal surface exchange capacity via agitation and adequate and effective circulation. Ultimately then the amount of co2 available for plant use at any given point is from what the plants respire (and isn’t off gassed ) plus any that is dissolved via gas exchange at the surface of the tank.


Hopefully nothing too controversial there.

We understand that comprehensive fertilisation, provided it is not many, many multiples of say, EI dosing (or commercial branded comprehensive mixes), and that 50% water is changed each week is neither a cause for new algae nor a fuel for algae that has already been established for whatever reason. Ok, so this statement has many potential holes in it but pressing on....

Could we say that if the above statements are true then the only lever we have absolute control over is light and that in a low tec/low energy planted tank, all else being equal, that reducing light duration (or more rarely increasing it) is the only way to bring about a balance in such an aquarium? Co2 or lack and/or fluctuation thereof is repeatedly cited as a cause of algae i.e. by reducing light we reduce photosynthetic demand until demand for co2 meets supply of co2.

For example, I currently have many forms of algae running concurrently in one of my tanks and although the light is only on 6 hours per day, if everything else above is a stated then reducing the lighting period further with the given light I’m using, is the only way I can a fundamentally address the imbalance that provoked the algae in the first place. (The existing stuff being plucked, scraped, snipped, nuked, nibbled and otherwise removed as a short term fix).

I’m not looking for answers to my own tank issues (I would follow the format rules and post in the Algae section were that the case), more for members to correct and fill in the vast gaps in my knowledge with a view to trying to produce a fuller understanding of how best to achieve a healthy, balanced low energy tank in a repeatable way.

Best wishes

Bg
 

Tim Harrison

Super Moderator
Staff member
Joined
5 Nov 2011
Messages
7,958
Location
UK
Light is really the only lever you can manipulate in a low-energy tank. In a high-energy setup it is the throttle that determines how much gas and nutrients the tank needs.

I think the key to a successful low-energy tank is to put the majority of the nutrients in the substrate and lean dose the water column when necessary. A nutritious soil substrate combined with Darrel's @dw1305 Duck Weed Index will allow you to do that.

In a mature tank with dense plant growth it's possible to increase the light intensity and duration. Maybe something to do with allelopathy, nutrient competition, and mutual shading appears to give higher plants the advantage.

But it takes patience to get that far low-energy, and choosing the right plant species in the first place is key. I always favour "easy" plants like vallis that can manufacture carbon from bicarbonates and have leaves that grow across the surface. And floating plants and plants that produce emergent growth, both have the aerial advantage.
 

ian_m

Global Moderator
Staff member
Joined
25 Jan 2012
Messages
5,204
Location
Eastleigh
For example, I currently have many forms of algae running concurrently in one of my tanks and although the light is only on 6 hours per day, if everything else above is a stated then reducing the lighting period further with the given light I’m using, is the only way I can a fundamentally address the imbalance that provoked the algae in the first place. (The existing stuff being plucked, scraped, snipped, nuked, nibbled and otherwise removed as a short term fix).
My mate had real algae issues in his low tech tank, after changing from T8 tube to T5 tube. In the end he fixed it by putting foil rings on the single T5 tube to reduce the light intensity by 1/2, whilst leaving the light on approx 6 hours. With frequent remaining algae removal, over period of a month or two, the algae disappeared. Odd spot appeared on glass and slight BBA on plants but he was happy.

Tank was far too dark for my liking with me using CO2 injection and 4 T5 tubes. :cool:
 

lilirose

Member
Joined
13 Aug 2020
Messages
283
Location
Ireland
I find that another "lever" that people overlook, especially in low-tech settings, is density of planting.

The most common newbie mistake I see is underplanting. If you have a low tech tank with a single java fern and an anubias or two, you will probably struggle with algae no matter what else you do, and might even come to the conclusion that you can't grow aquatic plants (I thought exactly that for 30+ years, so I am not immune). If you add as many low-tech plants as you can cram into the tank, it's a lot easier to keep it in balance, in my experience.
 

dw1305

Expert
Joined
7 Apr 2008
Messages
10,943
Location
nr Bath
Hi all,
that reducing light duration (or more rarely increasing it) is the only way to bring about a balance in such an aquarium?
Light is definitely the driver of everything else, but you can always control light intensity, even when you can't control light intensity with a dimmer, by adding floating plants, as a <"net curtain">. Personally I like a long photoperiod and a reasonably bright light.

Floating plants eliminate CO2 availability from the equation and they are plants adapted to <"intense sunlight on Varzea lakes etc">. So you have also taken light out of the equation (unless your light is so dim on full power that not even floating plants receive enough PAR to grow).

That just leaves the <"fourteen mineral nutrients essential for plant growth">, and that is where your floating plants come in useful again, via the <"Duckweed Index">.

It isn't very exciting as an approach, but by isolating each of the separate factors;
  • Light,
  • CO2,
  • Nutrients.
It allows you to eliminate them one at a time when you are problem solving. If you have a bright light and your floating plants are
  • yellow,
  • have stunted leaves or
  • don't grow at all,
<"it is a nutrient issue">.

If you floating plants have yellow stunted new leaves, it is a problem with a <"non plant mobile nutrient"> and you need to wait a little while for an improvement in plant growth to occur.

For the plant mobile nutrients as soon as you've added the nutrient limiting plant growth you should see a difference. With nitrogen the greening effect can be observed with in minutes for many plants, they visibly go greener as you look at them.

cheers Darrel
 
Last edited:

Driftless

Member
Joined
4 Jul 2020
Messages
59
Location
Chicago-area
I am with Darrel I like longish photoperiods with bright light and have floaters in over half of my tanks.

I don't think that we should overlook flow in this discussion in so much that any diminished flow from your preferred settings usually means that it is time for filter maintenance. I always put my hand in front of my tanks' outflow(s) to measure the pressure. Sometimes the filters needed to be maintained before our "scheduled' maintenance date.
 

PARAGUAY

Member
Joined
13 Nov 2013
Messages
1,834
Location
Lancashire
Such as Tropica and Dennerle will be working on the basis of this in there labs l would imagine all the time and conclude what are the ideal conditions for different plants. In the home aquarium IME it's often difficult to work out. Why is tank A doing well and tank B not so well? Interesting when George Farmer visited Marc at mdfishtanks he concluded his success with plants mostly low tech non CO2 set ups was a combination of his water being soft indirectly adding good CO2 with his water change regularity and maintenance. Noting that he is a user of duckweed too
 

dw1305

Expert
Joined
7 Apr 2008
Messages
10,943
Location
nr Bath
Hi all,
his water being soft
My guess is that a greater range of plants will thrive in water with low carbonate hardness and, as you say <"CO2 will be more available "> and a lot of nutrients are <"more available at, or below, neutral pH">.
..........Because of the hardness your pH is probably on the high side, this can limit the availability of certain important nutrients, in your case it will likely be Iron, Manganese and Zinc........
Many plants can use <"bicarbonate (HCO3-) as their carbon source">, Diana Walstad, and many of the people on this forum, have <"had great success with hard water">, so it definitely isn't a deal breaker.

cheers Darrel
 

Big G

Member
Joined
20 Apr 2020
Messages
80
Location
London&Thanet
Interesting responses and most gratefully received.

UKAPS truly is a special place for us to discuss these things. Almost without fail when it comes to an aquarium related topic, be it equipment, technique, flora & fauna, science or otherwise, my search string always has ‘UKAPS‘ tagged on the end. Someone here will have had something to say on a given topic.

On reflection the other variable I might well have left out is patience (if that’s not a little too philosophical) for a damp Saturday morning.

Changes take time to shake themselves out. Especially where processes are not being unleashed with huge availability of co2. As beguiling and compelling as some of the youtube videos are from known pro’s we all know and respect, they have to churn their tanks to produce new content and we do not. The option to tweak one variable in isolation and reflect on its impact say, three to four weeks down the line, is possible for us and i’m increasingly convinced is the foundation to building a sustainable personal knowledge base of technique in the long run.

With that in mind I’ve drop my lighting duration to 5.5 hours for a month and got some Frogbit. If the Frogbit flouishes I’ll give a little more light back. The other plants will also continue to grow with luck. I’ll take remedial action on whatever unasked-for algae turns up and see where we are in three weeks. In the end, along with the excellent support and advice available on this site, that’s all we can really do I think.

Hope everyone has a peaceful weekend.

Bg
 

dw1305

Expert
Joined
7 Apr 2008
Messages
10,943
Location
nr Bath
Hi all,
With that in mind I’ve drop my lighting duration to 5.5 hours for a month and got some Frogbit.
Definitely the Frogbit, but then again I'm a <"Frogbit obsessive">, and treat this forum a bit like "Frogbit Anonymous"................"My name is Darrel, and I am a frogbitaholic" .

I wouldn't shorten the photoperiod, in fact I wouldn't ever go under eight hours.

Even with an eight hour photoperiod you have 16 hours of darkness. The sun at the equator is <"incredibly bright for potentially 12 hours a day">, every day of the year.



If you go down to 5h 30min you then have 18h 30min of darkness and I can't see that can possibly be to your (or anyone else's) advantage.

cheers Darrel
 

Big G

Member
Joined
20 Apr 2020
Messages
80
Location
London&Thanet
Yes, your Frogbit index has convinced me Darrel. :)

The rationale for messing around with reducing the photoperiod further is that it is an attempt as laid out above to bring demand for co2 into balance with supply of co2. It is of course perfectly possible that I have reduced the photoperiod too much and the situation is the reverse i.e. that it is an excess of under-utilised co2 that has awakened the gremlins from their slumber.

I can’t argue with your reasoning about equatorial daylight availability however were we to follow the reasoning above then it may be argued that it was the disparity between supply and demand for co2 that provoked the algae to manifest in the first place so a shift in that metric is the only fundamental way to correct it...either way (see earlier).


Would the soft water you use have a naturally higher residual co2 level? (I believe GF pointed this out as a variable in regard to MD’s incredible achievements- just outstanding energy, creativity and enthusiasm must also play a part- the old golf saying, ‘The more I practice the luckier I get’ so to speak) Would also your mature tank full of plants be another factor? Tracy Island aka my non-co2 tank is in hard water and whilst it has quite a lot of ‘clumps‘ of plants none of them are particularly well-established nor voluminous at this point.


It must be said I have the utmost respect for your knowledge and ceaseless commitment to providing a long stream of beginners like myself with support that I have no right to expect. I feel the same when I read similar generosity amongst members sharing their experiences and advice. Investing the time to read such exchanges - I have frequently benefitted. In that spirit I will , from today, do the following;

Increase my photoperiod by half an hour each Saturday by half an hour, starting today (I believe doing more is not wise per week (Rubisco adaptions?) unless you think otherwise in which case I’ll dial in up to 8hrs from the get go).

All of my maintenance, fertilisation, heat settings and what not I will not change unless the Frogbit indicates ill-health.

It should be an interesting case study if nothing else and of course, it almost goes without saying than I take full responsibility on myself for whatever happens.

I don’t really want this thread to be about my tank per se but more as another catalyst to exploring some of the much discussed principles and fundamentals we adhere to. I’m sure results won’t be groundbreaking or conclusive in any way but if nothing else hopefully it will provide some curiosity and encourage further talking points on fundamentals. I hope this is of interest to other beginners like me and amusement to our more experienced members who have no doubt seen this sort of thing a thousand times and more :)

kind regards

Bg
 

dw1305

Expert
Joined
7 Apr 2008
Messages
10,943
Location
nr Bath
Hi all,
.....I can’t argue with your reasoning about equatorial daylight availability however were we to follow the reasoning above then it may be argued that it was the disparity between supply and demand for co2 that provoked the algae to manifest in the first place so a shift in that metric is the only fundamental way to correct it.
That is why I like a floating plant, it takes CO2 out of the equation, and many of them are adapted to <"very bright sunlight">. These (below) are from a Varzea lake in Amazonia, where they occur with extremely tricky" turned up to 11" plants like <"Ludwigia sedioides"> and <"Victoria amazonica">.


Would the soft water you use have a naturally higher residual co2 level?
Yes, more of the <"Total/Dissolved Inorganic Carbon (TIC/DIC)"> is in the form of CO2, but there is the <"same amount of DIC in total">.
.....another catalyst to exploring some of the much discussed principles and fundamentals we adhere to...
Yes, it would be brilliant to actually understand what was happening in the aquarium. I'm not sure any-one is going to be able to <"provide empirical proof">, there are just too many variables, but we can get closer by writing about what happens in our aquariums, what works, and what doesn't.

cheers Darrel
 
Last edited:
Joined
30 Aug 2020
Messages
126
Location
Bristol
Having read your convincing thoughts @dw1305 I think I might up the photo period a little and maybe the intensity, do I do both together though or use the acclimatisation program and let intensity increase over 2 weeks?
 
Similar threads
Thread starter Title Forum Replies Date
B My low tech tank El Natural & Low Tech 1
Angelfishguy99 Low tech and EI ferts El Natural & Low Tech 15
Tom Raffield New Low Tech Tank El Natural & Low Tech 7

Similar threads

Top