Plants having problems with certain growth heights

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Jaybird

Aquarium Advice FINatic
Joined
Apr 6, 2006
Messages
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Location
Ottawa, Canada
My tank doesn't have any CO2, but I do put in some liquid plant stuff every once in a while.

The problem I seem to be having is that most of my plants have differing height problems. None reach to the surface, and some tend to grow well to three inches and others to about seven. After that they try to grow but the upper portions end up dying away.

The tank originally came with only one fluorescent bulb, but I switched that to have two because not enough light was reaching the bottom of the tank with the one bulb.

Is it possible for the plants to be receiving too much light?
 
before anyone can really help you you need to give this information...

~Plant(s) affected?
~Tank size/volume?
~Lighting/wpg?
~Do you inject CO2? If so do you know the level?
~What do pH, KH, PO4, NH3 and/or NO3 test kits say?
~Dosing? What/how much/how often?
~Heavily, moderately, or lightly planted?
~Fish stock?
~Tank Location (near windows - in direct sunlight)?
~How long has tank been set up?

A pic of your tank or the plant affected will also be useful.
 
Well, here is the information that I can give:

- plants affected - (the only one I know by name is Amazon sword, the others are varied)
- tank size - 90G
- lighting - each bulb is about 30W, so that makes it about .666 WpG
- the only CO2 is from the fish :)
- my water is very soft, so my KH is probably low, that's why I use the liquid plant fert. Ph is around 6.8 - 7.0
- I dose with the liquid plant fert once every two weeks.
- moderately planted
- fish stock - various new-world cichlids (nobody destroying plants purposefully. Occasionally there are some that get uprooted, but they are quickly replanted)
- tank location is not in direct sunlight
- tank has been setup for 5-6 months now

Here's the tank from a while back. http://www.aquariumadvice.com/download.php?id=20597 It's changed since then (No Internet at home right now. When I do, I can post a picture). The sword behind the driftwood is still there, but the small sword-ish plants to the right are gone. I have put some more plants in, but I don't know what they are called.
 
Do the leaves on the amazon swords turn kind of transparent after a while? If so then it is a sign of insufficient light.

In anycase, I am guessing that you don't have enough lighting. 0.66 WPG (actually its a little higher due to rule breakdown on larger tanks but its a moot point) is not a lot of light. You were right to upgrade it, but 0.66 is still below the light threshold of most plants.

Two things you could do, and I recommend doing them both.

1. Inject CO2. This will help plants better utilize the available light, allowing you to keep plants in lower light settings than "normal". I've kept an amazon sword at about 0.55 WPG with CO2 injection...though it was right on the edge of dying all the time.

2. Further upgrade lighting. There are many things you can do here from buying a CF strip to adding more NO Fluorescent strips to ODNO your bulbs. Whatever you do, it'll help.
 
Not enough light. Swords want 1wpg minimum, really do best at 2wpg or more.

injecting CO2 won't help at this point, light is your limiting factor, no question about it. you likely don't even need to fertilize if you do weekly water changes...you just lack light.
 
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