best light to grow macro

Another thing, growth rates of individual tanks vary. Often times greatly.

So while a 5000K cheapo light can work pretty well for a small fuge supporting a relatively light bioload on a large main tank, they may not be able to maintain the same balance on larger tank or a tank with more bioload, feeding etc.

So while it might work for one person, the same thing may not for the other. Understanding why is a key to seeing the difference.

I'm more interested in the "whys".

Some tanks need nothing, just a fuge to work well and little light.
Some need more tending.

Generally, folks want a simple operation. This has much less to do with plant science or growth and a lot more to do with social sciences.

But there are trade offs, you can get higher NO3/NH4/PO4 removal, but is that always a better thing?

I think many reef folks assume it is and I would certainly challenge this very strongly.

Some PO4/NO3/NH4 ain't bad.
You can go too far with obsessions there also and that's not good and limits growth not only of macros, but of the corals, they have algae inside them BTW and those algae use the same things all other algae use to grow.

Likewise, we can go too far the other direction, too much PO4 and NH4, I honestly do not know what too much NO3 really is, few reef folks are willing to have a nice balanced reef and progressively add more and more KNO3 till they get a negative response then repeat it 5-6x to verify the effect.

Blah blah blah blah all day long, but I've not met anyone that's done this simple test to see. However, I grow macros, not coral. If I was interested, I would kill and torture some coral to see. Then I'd know instead of assume and guess. Not many empiricist around in that group unfortunately. I'd rather kill and grow seaweeds.

I've gone to about 30ppm for macros , no issues.
So what I'm getting at, there are ranges of optimality for our habits, routines, equipment, set up, methods that best suit a particular goal.

Some are cheap and want to go a bit more low tech.
Some want to maximize things and get the most growth rate out of it.

Comparing them both as equal is not particularly a logical assessment. ............You are comparing two different goals.

It all starts with the goal.

I prefer to focus on the macros for the goal and scaping and health of as many species as I can get my grubby hands on.

Most fuge folks could care less as long as their NO3/PO4 are in their pre set ideas about what "should be" and that is a radically different goal.

Still, one goal does not invalidate the other, and we can learn more about one method using the comparative approach if we are careful to keep in mind the difference in goals. they have some very real and relevant trade offs.

If you can understand why the slow growth and the fast growth work and how to achieve that, then you can understand each method and growth rate in between.

I seek to make macros grow at the fastest maximal rate without noxious pest algae. A basic clear goal. So I use a number of methods, high non limiting nutrients, high light, high gas exchange and different methods that make doing this easy.

Now I can slow these rates down easily by reducing light as my limiting parameter and manage the growth rates of the fuge, or main macro scaped tank easy enough.

Generally, this is easier than reducing PO4 or NO3. And it cost less to do. So that's a good trade off.

50-100 micromoles should be plenty for most macro algae, I use 450 for my tanks, but I know I'm after a faster rate of uptake and add ferts and tend the tank more. If something goes wrong, then it will happen faster with higher light. I do not want to wait if I'm trying to learn something, I want things to happen fast so I can answer the question before I get old and not have the make sure I have all my parameters in order for too many weeks. That's a lot of work.
If I can balance a high light, high nutrient planted tank, then slowing things down ought to be relatively easy.

So less light, as least as far as macros are concerned, means more stability and the ability to maintain lower NO3/PO4 without bottoming out so hard.

Not a bad trade off there.

I think many folks end up missing their goals by adding too much light to the fuge and driving the macros too fast.

Then they never get the ecosystem function they desire(often nice low NO3/PO4 over long time frames) from the fuge and it is either feast or famine (very rapid uptake and then followed by a crash).

This the balance concept.
Understanding it and why it works, the meat and taters of it, is not discussed much if at all here and elsewhere.

Sit down and try and wrap your heads around it and give this some thought.

It's all about the rate of inputs/uptake/export and maintaining a stable range.

What determines those rates?
Then you can start answering things.
Light, nutrients, Carbon, Ca, CO3 etc etc

2700K might actually help and be better if you had a lower rate of input vs another light say the 5000K.
Likewise, on a higher rate tank, more micromols would better balance things + more trace dosing, perhaps some added aeration and even some NO3 dosing on the side.

Being able to move from low to high tech, slow to high growth rates is a goal anyone really interested in helping folks in the hobby over a broad range could consider. It's a general understanding that allows you to use most any, modify a method, create a new one etc.

Rather than "either or", you two folks appear to have different goals here.

Much like the arguments for non CO2 vs CO2 enriched FW planted tanks, they both work well and they both have much different growth rates, about 10-20X difference.

I suggest you try both methods, then you'll know, but I'm a bit of an empiricist...............

And generally am left to test my own nutty ideas...........
But as they say.........today's mighty Oak was once yesterday's nut that stood it's ground


Regards,
Tom Barr
 
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wow that was confusing. I am looking for a stable environment that will help remove nutiants and other things that I don't need in the tank, so I can do less water changes. I am setting up a reef tank. so what do you think?

The refugium is a 55 gallon tank cut in half the other side is my sump. the display it a 125gallon system.

Roger
 
I'd likely use a 55 w A&H supply kit or a cheap PC 6500K range 55-65 W bulb.

I'd also suggest using several species of macros, not just one.
That will remove a significant amount of waste.

A trick you may use is a scuffed clear lexan or acrylic plastic to reduce the light intensity if the nutrients drop down too low(assuming you can and do measure them accurately) or raise the light up etc.
Metal screen also works nicely and you can add more layers as needed.

I think simply maintaining the plant biomass at a manageable level and not allowing it to grow 2-4x in size will also help a lot.

This keeps the uptake rate and growth stable rather than feast or famine.

Plants do best, like any filter, when the supply of waste and the uptake/removal/export is kept somewhat constant.

If you go from high to low to high to low, that's no good for the main tank either.

Nor is it good if you grow macro's alone as their own tank.

You need to figure out how much waste is produced by your tank and tweak things as needed.

Your goal is to balance the rates of waste production and the growth rate demands for nutrients of the refuge.

There is no one simple method for that, it depends on the main tank's loading rate.

I've offered up some methods to slow or increase the rate of growth and how to keep it stable.



Regards,
Tom Barr
 
<a href=showthread.php?s=&postid=10114749#post10114749 target=_blank>Originally posted</a> by Plantbrain
I've virtually always seem far better growth with a dark phase.
Other things such as moving the plants/bottoming out the Nitrogen supply , low Ca etc seem to cause issues.
Perfectly explained in your first post, Tom. From what I've seen in my own tank, dark phases are always followed by boosts in growth from algaes. Important nutrients to watch out for: C, H, O, P, K, I, N, S, Ca, Fe, Mg. You may find you need a micronutrient trace mix along with Ca and Alk supplementation to achieve your nutrient export goals. This is especially true if you really want to boost your export. Similar to what piercho is talking about without the high light.

That is a good choice on the PC screw bulb. If that doesn't work to suit your needs, you may try a 1 or 2 bulb 24W T5 6500K. With the SLR and the efficiency of a T5 bulb, you'll be able to get your money's worth and it will provide impeccable light for the plants.

What species of algae were you considering for your vegetable/algal filter? Like Tom says, diversity will be your friend to have the most efficient filtration.
 
Good point on the T5's.
I've noted that it might take 2-3 weeks before the traces add a real effect, you must dose at least 2-3x a week consistently to see results here.

I get very dark red or green coloration when I do.
I also see the rates of uptake increase significantly, more so in marine systems than FW. I think it's namely due to the scarcity of traces in the marine systems vs the FW systems.

Those trace metals form the main parts of uptake and metabolic pathways and without them, the macro cannot really do much.

In a huge massive system, then sure, there's a tiny trace that's always available. But in dense small system? Nope.

The macros just slow their growth and uptake down to match the most limiting nutrient. So while not dosing traces can work and many never bother, the ability to enhance and optimize a Reef/refuge/macro tank is still very much present.

Some folks are quite happy doing 20mph, and having never gone 60mph, they may have little idea.

But 60mph is a two edge sword, things will rapidly crash if you stop adding the import(traces/Ca/Alk/NP etc) and export(pruning water changes etc)

So this is not without a trade off.
Always have those where they be $, export rates, water changes etc.

The main issue we muddle through is trying to figure out which of these services best suit us for our goals as owners of aquariums.

I see many folks argue and carry on, myself sometimes as well :lol:
without realize that the 2 people have very different goals and expectations.

I do however try to be aware.
But like most folks, I'm very much human and prone to a feeble mind and lose track of my keys, brain, wallet, time you name it, I've lost it.
So I have to check and recheck everything.
I have less confidence than in the past certainly.
But what I do know, I know well.



Regards,
Tom Barr
 
<a href=showthread.php?s=&postid=10238275#post10238275 target=_blank>Originally posted</a> by WarEagleNR88
What species of algae were you considering for your vegetable/algal filter?
Here's an idea from Inland Aquatics: Refugium Flora and Fauna Kits. I've never ordered from them but I plan to one day. They've got some good stuff as far as macroalgae and cultured invertebrates go.
 
Personally, I use my eyeballs. There are a few variables here and there--placement, water flow, aeration--but otherwise if all nutrients are exactly where they need to be, you'll have explosive growth from these plants under any light. That is typically why people have problems with growing algae, one of those variables are off and it is most likely nutrient based. And don't think you're the only one around who will have this problem. I have it all the time. It's really a game of trying to figure out what your tank needs--especially if you don't regularly or can't test for those nutrients you're interested in. Growth will be the indicator of rate of uptake.
 
You can measure uptake a few ways.

Test kits, dry weight and tissue analysis etc.

The issue folks need to address: DBS's will remove some NO3 as N2 gas.

Uptake does not = growth, due to luxury uptake etc.

I suggest calibrating a test kit before doing anything and measuring over week time frames.

Or you can make uptake assumptions based on other folk's data.
Say 2 ppm per day NO3 in a packed tank.

I do not think we need to go over that amount
Macros rarely would ever require more than that.

Regards,
Tom Barr
 
May have liked the warmer reds in the spectral output and also the more intense focused light area vs a more linear long diffused path.

The other issue can be the other limiting factors beside mere light.

You have 3 main things, light, CO2 and nutrients that cause the weeds to grow. So adding more light places more demand on CO2 which places more demand on nutrients.

Adding more light intensity may produce high CO2 demand which if not met, can stunt the growth. Adding more light may also stunt the weeds by havig enough CO2, but quickly running out of NO3 and having feast of famine rather than and nice stable concentration of nutrients allowing the weeds to grow stable and well.

Getting better growth using less light is a very common observation.

Why?

Because you reduce the demands of CO2 and nutrients, slowing down the growth, allowing more time to acquire and assimilate these into plant/weeds tissues.

If you remove those limitations and add more light, then you should see more growth until you hit a light saturation point which can be quite high.

Thus correlation does not imply causation.

We can be fooled by these observations and assume that less light or so an so light bulb works "miracles".

Still, many folks add a heck of a lot of light on their planted systems.
Then they quickly run out of nutrients/CO2 and the plants crash on them.

At low light, you will have good results, you might be able to get more export out a refuge with more lighting, but you can add a light here and there step wise and rev the lighting up slowly anfd you will have more success.

As the plants/weeds start to show signs of nutrient stress, you back off the lighting some.

This allows you to control the rates of growth and still have awesome, healthy growth and stable refuges.

We really have few options for controlling lighting.
I use s aseries of screens/shade cloth to reduce some systems, a few have rheostats, a European company makes a variable T5 system that's awesome, but we do not have such systems here.

Of all the parameters we ave to control plant/weed growth light can be the most stable and easiest to control.

NO3? PO4? CO2?

Not even remotely as stable or controllable nor as easy to measure/test.

Nice thing about the 19 w PC flood lamp: cheap, easy to add progressively more of, good for tight spaces, not too much light.

2 green thumbs up.


Regards,
Tom Barr
 
well what about if you add more light in the main display does that effect the CO2 level?

also what are signs of nutrient stress look like on the plant/weed?

Thanks Roger
 
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