What do you think is causing this type of growth in my Downoi?





I have it in a 55 gallon tank with ADA Aquasoil
I dose EI religiously
i have 4-55 watt 9325K GE PC bulbs on for 8.5 hours a day
I have pressurized CO2 with a pinpoint controller
My Ph is set for 5.7

HC is doing well
Utric is happy and spreading fast
But I am not sure why the downoi is growing with such large separation between the leaves.

I posted this on The Planted Tank Forum without much luck, Thought I would
try it here as well.
What are your thoughts?
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My initial thought is too short of a photoperiod. I've had success with 10-11 hours...in my anecdotal experience when I see large gaps between nodes it is often a lighting issue.

Tall P. helferi, IMHO, is likely a result of low light.

I would say light as well, but you have loads of light above the tank. Is the plant in any major shadow at all?

I woudlnt say that your photoperiod is too short.. lanky growth is more a sign of insufficient light intensity, rather than anything else.

If you have no shadows, maybe your tubes need cleaning, PC tubes do get pretty mucky after a while.. might be that unless theyre really really old ones, but even then, you have so many of them I doubt that would be it.

Try 10 hours and perhaps a 5000K bulb in there as well.
You have tons of light and this is a low light plant.

Regards,.

Tom Barr

Thanks all will give 10 hours a try.

Hi Tom,
I've got some of this and I'm also finding growing quite leggy. According to Tropica it should grow bushy given "good light conditions and a substrate rich in nutrients"
At the moment it in an open area of my 30G under a 70w MH.

Are you saying you get best results with less light or a bit of shadow?