Do Any Plants Need 'high Light'

[SuperColey1]

People who have read my threads/posts on here (and often told me I was wrong ) will know I am not a believer in the high light plant theory and that I have long speculated that I think it is probably due more to the levels of CO2/ferts that are used in conjunction with high lighting.

If you have read my threads/posts you will know that although I do have supposed 'low light' plants I have rampant growth from them and am constantly having to hack away at them. For those that don't I'll fill in the gaps:

Tank : 125Ltr tall (18" height)
Lighting : 0.9WPG T5HO 4500K for 8 hours a day. 0.5WPG T8 6500K for the central 2 hours
CO2 : pressurised injection stable at 30ppm
Ferts : Full EI (as per high light quantities)
W/C : 50% weekly
Circulation 17.6 x tank volume per hour (2200lph)

The thread I link to below seems to suggest that when I and a few others speculated it is high CO2/Low CO2 rather than High light/Low light that we were right!!!

One thing it seems I was wrong on is that you don't need high light for carpeting!!!

http/www.barrreport.com/general-plant-to...s-who-knew.html

7 Pages but well worth the read. Any thoughts / discussions? Of course I love being proved right on these things but I will not gloat because I was wrong on carpetting plants needing high light

AC

 

[nosoup4you]

Wow Andy...and just when I thought that I was beginning to figure it all out. Looks like I'll be starting a new project in the future....

 

[SuperColey1]

I've been harping on about several seperate theories over the last year or so.

1) More tubes is better than higher wattage because of the light spread i.e. 4 x T8 gives better spread than 2 x T5 even if equal total wattage

2) T5 is as much as 2 x T8 due to efficiencies and restrike issues

3) That the high light plant is a myth and that it is the conditions people apply in a high light tank that are the key.

The first 2 are quite contradictory to the logical thinker but what I meant is that with more tubes you can space them front to back whereas if you choose to go with less tubes of the same total wattage then it is not as good at spreading the light from front to back.

The T5 = 2xT8 is the only one I can virtually say I've 'proven' because I can see the difference quite clearly between the growth of my scapes under T8 and under T5 of the same total wattage. In fact the T8s were slightly more at 0.91WPG compared to the T5 which is 0.9WPG

The better light spread from the 2 T8s compared to the 1 T5HO could explain though why I was able to grow Riccia carpets and get them to pearl under such low light!!! I can't say this for sure because I haven't tried it under the T5s nor am likely too. Riccia was the in thing and I grew it for a while before getting bored with it.

But seeing this article it clears my mind a little in that it has brought all of these 3 together into the same argument.

The article is saying that these tanks using ADA Metal Halides (HQI) are low light. However the large reflector and light spread from the MH is what is giving the success. It doesn't need to be higher because the spread of light is what is giving the success.

Hopefully when I finish my LED setup I will see similar results as 15 LEDs at 1.3WPG will be spaced much better. However I am anticipating having to raise the lights significantly from the water surface as 8.4W was as bright if not brighter (to the human eye) as the 18W T8!!!!

We shall see.

This is why Tom is good for this hobby. All of us can theorise rightly or wrongly which is part of the problem of why there are so many myths around. Some people can afford to test but don't. Some don't want to because they have disciples for their theory and don't want to lose their 'higher' status. Tom theorises and then says 'but why' and gets stuck in finding out why. If he is wrong he doesn't mind saying so but he rarely is.

There are others on some other forums that love their disciples and therefore defend their theory as fact and get very defensive when it is questioned without ever being able to prove they are right because they have never tested.

Unfortunately I can't afford to do these tests so I can theorise what I like but have to wait for others to prove me right or wrong. I try to make it clear that my theories are just that though and not proven. Therefore I do much more reading and watching than practical science. lol.

Got to find something else to theorise on now. lol

AC

 

[Dave Spencer]

I`m still not convinced about HC though. The moment any of mine gets shaded it starts reaching for the surface.

I guess all plants have a minimum amount of light whereby they start to deteriorate, but none of them need as much light as we think. I have a new 240l tank using two T8s, plus a third for a midday burst. This is definitely lower light than my 120l which had 108W of T5s, but I reckon HC would do well in it and stick to the substrate.

I would love to see the phrase "heavy root feeder" disappear for plants such as crypts. Whilst my choice is to use ADA Amazonia alongside EI, I have no problems growing crypts in Amazonia or an inert substrate.

Dave.

 

[aaronnorth]

I`m still not convinced about HC though. The moment any of mine gets shaded it starts reaching for the surface.

Mine too, it takes ages for mine to grow in a small patch beneath my diffuser, perhaps i should move it further up the tank lol.

 

[pippoodle]

my plants in my 24" deep aquaone grow like mad

i'm always having to cut them back
i dont have any co2 in there and only dose fortnightly with tetrapond plantamin

the moss on the bottom of the tank on a piece of bogwood reaches up 6 inches within 3 weeks so then i nip it off and move it around to my other tanks

my plants have grown like mad ever since i've had the floating amazon frogbit cutting out some of the light
they are strong aswell not stringy stalks with just some bits of leaves here and there like i have seen in some tanks

in my tanks i have i have cabomba , vallis , spiral vallis , amazon frogbit , riccia , java moss , christmas moss , java fern , Mayaca sellowiana , marimo moss balls and some other plants i cant find the name of

all tanks have at least one 50% water change every week and are fed with tetrapond plantamin plant food every 2 weeks also dosed with hikari shrimp mineral every 2 weeks

rio 180 has 2xt8 30w 36" lights on for 10-12 hours
rekord has standard t5 10 - 12 hours - this tank has nutrafin co2 in for 1 week every month
55 litre hex has small 5w tube 0- this tank also had nutrafin co2 1 week every month
aquaone 620ar t 0- PL18W Triphoshor / Bio-Lux Mix 7.1K / 14K - takes 2 of these - <a href="http/www.aquarium-parts.co.uk/acatalog/i..._AL_T18WTB.html" target="_blank">http/www.aquarium-parts.co.uk/acatalog/i..._AL_T18WTB.html</a>

i must be doing something right and would like to know what

cheers sarah x

 

[Truck]

im with you on this SC1, i have seen thousands of articles on PFK etc on the ADA tanks, and alot of them are growing HC and glosso as a carpet plant with as low as 1.5WPG, they are using the estimative index method like you and around 30ppm of CO2, and all of them are thriving, ive seen many tanks with HC and Glosso carpeting under as little as 2WPG T8's!

im going to try it in my new tank, and i will keep you posted

 

[SuperColey1]

Those ADAs are apparently less than 'the equivalent' of 1.8WPG when the reduced output is taken into account!!!

Dave - Further on down the thread they are talking about the HC and I think they come to the conclusion that all of those scapes are quite low with minimal shade. this may explain it. I always had my Riccia right at the front under the 1WPG T8 so it was never shaded at all.

You've reminded me of another 'harp on' I have had so thats four although this is unrelated to the light issue. I am like you in disagreeing with the 'heavy root feeder' theory. There are far too many inert substrates having success with supposed 'heavy root feeders' for me to believe it. Amazon Sword is normally one of those plants that people who only want a few plants in their cichlid tank use and they look very healthy.

I don't even agree with the 'root feeding being their preference over water column' statement but this one is not so important really. Nutrient substrate or not it doesn't really matter if someone wants to believe this one unless we want to get rid of the 'Must use root tabs' for this plant suggestions.

Tom has called Glosso a low light plant for a long time.

I may try Glosso once I get the LED setup in but not HC. Not keen on the colour which is one reason why I got rid of the P Helferi and probably one reason I went off Riccia. I prefer the darker lusher greens to the bright almost luminous greens

Much as I would like to test things out after reading this I only have one tank and want to keep things that look good together (to my eye) Glosso may fit in better but I'm not overly sure about wanting it taking over the foreground.

AC

AC

 

[nosoup4you]

After reading the thread at the Barr report, I have decided to forgo the DIY reflector (ATM I only have what came with the hood) that I have been researching and just deal with the loss of light. My plants seem to be happy with what I have and if it means less ferts/maintenance then I am happy as well. Without a proper reflector and 2x 13w CF (10 gallon) , what kind of light do you suppose I am actually getting?

 

[Dave Spencer]

Much as I would like to test things out after reading this I only have one tank and want to keep things that look good together (to my eye) Glosso may fit in better but I'm not overly sure about wanting it taking over the foreground.

AC

I like to trigger various alga in my tanks just to prove theories to myself before I "harp on", but like you, it isn`t practical with your pride and joy in the living room. Having said that, I can "harp on" about BBA, staghorn, exess/deficient nitrates and phosphates and trying to starve alga from a lot of my own personal experience and observations....BBA and staghorn usually from not noticing when a CO2 bottle runs out.

It is good to see when people actually observe what is going on in their tanks and drawing conclusions, instead of quoting some professor with a PhD in supercallifragillistics who has studied some water way in Florida in 1930, and comes to the conclusion that high phosphates cause algae, without realising there already was an algae bloom and all he did was feed it.

Let us be thankful for the work people like Tom Barr carry out.

Dave.