plant leaves change

[rpddink]

I have two plants in my tank and the new leaves are growing in a diff shape than the old.
Old leaves had a round oval shape and the new ones are growing in long and narrow.
Anyone seen this happen before or know what makes it happen?

[mewickham]

What kind of plants? Many of the plants we keep in aquariums have two forms of leaves, depending on whether they were grown emersed or submerged. Often, growers grow the plants above water. It gives faster growth for quicker propagation. When you put such a plant underwater, the new leaves will grow in with the submersed-form leaves. The older, emersed-grown leaves, may even drop off. The differences can be dramatic between the two forms. Water wisteria, for example, has a broad, sawtoothed, crisp, hairy leaf when grown above water. Submersed growth, though, produces smooth, soft, highly fingered leaves.

The amount of light is also a factor. Stronger light makes larger leaves, more compacted on the stem. Stonger light makes some species' leaves red. Even the strongest aquarium lights don't approach the strength of direct sunlight. So even well-kept plants may change form a bit from what they look like upon arrival.

[dennysfishroom]

I'm assuming the rule of thumb is for florescent bulbs. Is it different for LED's? Also what wave-length is best? Denny

[rpddink]

Im not a guru like you guys - but have been reading a lot on light vs. tanks vs. watt vs. color .
please tell me what I have wrong (and I know I am wrong a lot )
One- I have learned that watts per gallon is as useful as liter to horsepower- it will only work if ....... well it will not work too many factors.
par seems to be best and its only so so right.
example --- a 100 gallon tank squared vs. a 100 gallon long

say you have 80 inches in length with recommended 2 160 watt bulbs @ 80 inches each = 4 watts per gallon "great to grow plants"

Now lets say the square tank is 40 inch by 40 inch with 4 80 watt bulbs @ 40 inch each = 4 watts per gallon "great to grow plants"

And now considering the bulbs are long and not a spot light -
the long tank is only going to have the "4 watts" per inch in length of tank and the 40 inch 8 watts per inch of length.
factors do come into play like width but math shows that its not as much as you would think.
The opposite
Get the 40 inch to 4 wats per gal and then stretch the light out and you are at 2 watts per inch of length.

second thing I’m learning is that t12, t10, t8, t5 ect are not wattage equal in lumen per watt out put and a t12 vs t5 is a 1.4 multiple

then what ballast you use is even more important ballasts are starting to under power (under drive) lights to be able to say that they are more "energy saver" than another.
also it seems that ballasts are multi function and will sometimes "overdrive " a t8 at 17 watts and under drive a a larger watt bulb but is listed as able to run all wattages. ( I am still muddy on this )
lastly (for now) Kelvin in fresh water seems to be over rated as plants love 2700k but makes a tank look yellow and bland so 6500k is more visually appealing.
Also trying to balance light vs. need for co2 as higher light levels lead to faster growth = more co2 and ferts.
Please, just trying to sort out myth from fact
The more I learn the more questions I have.

[rpddink]

So yes I agree I probably need more light but just want to understand and do it right.
here are some pics of my tank
Think the plants have been in for about 8 weeks

[rpddink]

the last pic is the leaf changer it is a echinodorus amazonicus

[rpddink]

well it looks nicer in person than the picture. need plants along the back wall ...... need plants to grow...... its still a new tank
dont be too hard on me

[mewickham]

Rick, you are right that watts per gallon is not an accurate rule. It is not a scientific formula and not meant to be perfect. It's just an easy to follow guideline. 40 watts of light on a 20-extra high has an entirely different effect than 40 watts on a 20-long. But that's why the rules is variable: 2-5 watts per gallon. Use 2 watts per gallon for shallow tanks. Use 5 watts per gallon for very tall ones. I like to do something like 2w/g for 12" tall, 3w/g for 18" tall, 4w/g for 24" tall, and 5w/g for 30" tall tanks. Even that does not follow the inverse-square rule, but it puts you in the ballpark of something that works. A rule based on lux, lumens, or par would be more accurate, but I don't believe many manufacturers list those numbers on the package. So there would be no easy way to use such a formula.

Kelvin ratings also have variable value. For starters, the manufacturers seem to just make these numbers up! I've seen "10,000K" bulbs that were blue, like actinic, while other brands of 10,000K bulbs are very white. What your eye sees is more important than those numbers. (The Kelvin scale itself is based on the color "an imaginary black body" would turn as heat is applied to it. It's a scale based more in theory than reality.) So find a good "full-spectrum" bulb and you should get good results. I have noticed, though, that certain plants will do better under different colors than others. My crypts take off under 9325K bulbs, but slowed down when I switched to 8000K bulbs. Vallisneria did the opposite. Changing back to 9325K bulbs, reversed the process again. But that doesn't mean that someone else's results would not differ. There are other factors that affect how well a plant does-- temperature, species, competition, water chemistry, fertilization.

Regarding the changed leaves on your amazon sword: These plants are grown hydroponically. That is, they are grown with the roots in the water and everything else emersed. It allows fast growth and is the only way to effectively reproduce the plant, since it flowers above water. When you replant the plant in a submersed state, the first thing it does is put out a bunch of new, submersed-growth leaves. Then the old leaves die and should be pruned away. Emersed leaves don't surive underwater long-term. This is the same for other swordplants, crypts, and most of the plants you buy in pots. So the change you are seeing is completely normal.

[rpddink]

Thanks for the reply Mike. Your watt per gal. based on height makes it clearer ( the deeper the more light you lose ?). The kelvin thing drives me nuts... I have been calling the bulb companys and the "listed" kelvin is imposible to get a good reading on. Seems like k is more an x/y axis than the used single axis. If you dig it seems you can find $3.00 non plant bulbs with as good color spectrum as $20.00 plant labled bulbs. Reflectors seem to make as much a s a 45% diff also. never had this much trouble growing tomatoes...

[mewickham]

Rick, the most important thing about the light is that more is better.

Your watt per gal. based on height makes it clearer ( the deeper the more light you lose ?).

Yes, because of the inverse square law: http://en.wikipedia.org/wiki/Inverse_square_law. When a thing is close to a light, it physically blocks most, and receives more, of the bulb's output. When that thing moves further away from the light, more of the light is able to radiate elsewhere, rather than toward that thing.

If you dig it seems you can find $3.00 non plant bulbs with as good color spectrum as $20.00 plant labled bulbs.

You may be able. Often bulbs sold for aquariums are the same bulbs sold more cheaply for household uses. However, typical household fluorescent bulbs, such as cool white and warm white, are not usually good choices. Common daylight bulbs can work pretty well. The best is "full spectrum" bulbs. These have some emissions in the near-UV range that tend to make them be better bulbs. But I'm really generalizing here.

[sskruzr]

I'm thinking when it comes to lighting for plants, what has worked for "you", under what conditions, gives people an idea of what to try. Personally, I had best results in a previous acrylic 180, 72" X 24" X 24" with 3 110w compact lights. I used Coralife's 6700k bulbs and had to thin the forest every month. The forest consisted of crypts, val, hygro, and hornwort. jm2c

[stpierce]

This was all very interesting to read and I went through many of the same questions a few months ago regarding 2 10 gallons I wanted to light in my room. I decided to go with regular screw in cfl and reflectors from http://www.1000bulbs.com/category/2-to-200-watt-cfl-compact-fluorescents/ This allowed me to play with different cfl bulbs and their results for much cheaper than other places and still get the benefits of reflectors. Just a thought if you are sort of the mad scientist type.