Ludwigia palustris what has happened to it

[Tetley2]

Hi this is my first post



Current setup is
Tank - 120 x 60 x 60
Co2 - pressurised 3.2kg tank, up Aqua inline diffuser
Filter - 1400lph
Circulation - hydor 2200lph, hydor 1600lph, hydor 1200lph
Lighting - 2 tmc 1500 tiles at 65% for 8 hours
Ferts - basic ei
RO water re-mineralised with seachem equilibrium and baking soda
GH - 7-8
Kh - 3
Drop checker light green to yellow

The plant leaves seem to be developing holes in them and just melting away, the holes go translucent and green first, not sure what's going on with this.

 

[Dr Mike Oxgreen]

How long has it been set up and planted? Could it be that the plants are simply adjusting?

Mind you, your light level seems rather low if my sums are correct. Am I right in thinking those lights are about 2000 lumens each, giving a total of about 4000 lumens? And you're running them at 65%, so 2,600 lumens. Converting that to the equivalent of T5 wattage (divide by 70, since T5 is roughly 70 lumens per Watt) gives about 37W. Your tank is about 113 US gallons, so your lighting is equivalent to about 0.3 Watts per gallon of T5 lighting.

Unless I've made a mistake somewhere, I would say you've got far too little light for any plants to grow. All the other characteristics of your tank suggest that you're aiming for high-tech, so you probably want about 2 Watts per gallon equivalent.

 

[Tetley2]

I didn't think lumens was the way to measure the light with LED, I thought it was PAR, but thanks for the reply.

It's been set up about 6 months now and had issues with co2 and flow but seems to be getting better with everyday now, I did have the light lowered to 30% and that was when a lot of my plants started losing leaves, since raising up to 80% now at 5% every other day it's really picked up, plus change to spray bar.

I think my problem with the leaves was that the plant was new (3 days in) and that I'm spot dosing easy carbo to kill my BBA which has really worked but might have got on them leaves maybe, I have just snipped them off and everything seems fine, new cuttings planted have double in size over the past two - three days

 

[alto]

tmc 1500 tiles

depending which tile this is

Specification is:

• 10x Cree XB-D Power LED’s – Natural Day Light
• Beam angle of 120 Degrees
• Correlated Colour Temperature of 6500K
• PAR at 400mm in air is 148µEinsteins/sec/mSq
• Illuminance at 400mm in air is 4430 lux
• Total Luminous Flux is 2058 lumens
• Total power consumption (including PSU) is 30W at 700mA
• Efficacy is 69lm/W

Specs on the "Colour Plus" tile is slightly different as different Cree LEDs are used

Unfortunately there is no PAR or PUR available in water 😕
- don't know of many folk wanting to use this sort of lighting in "air" so can't figure why manufacturers list "air" data
& zero "water" data

 

[Dr Mike Oxgreen]

I didn't think lumens was the way to measure the light with LED, I thought it was PAR, but thanks for the reply.

Lumens are a sensible way to measure output for any type of light, and allow you to compare different types of light technology. PAR would be even better because that is a measure of the wavelengths most efficiently used for photosynthesis, but the figures are rarely available. If you think lumens are not applicable to LEDs then you have misunderstood something! 🙂

With the amount of light you've got, I think you'll only ever be able to grow the least demanding plants. Perhaps right underneath each light you might have enough for plants requiring slightly higher light.

 

[rebel]

Can we have a look at a full tank shot, close ups of all plants and growing tips?

 

[alto]

From George's TMC Signature journal

TMC Signature 60x45x30cm

2 x TMC GroBeam 1500 Ultima (6500K),

It's about 60cm from the water surface. <snip>

The PAR is still almost 50 across most of the substrate

These are the only PAR measures I could find for the lighting ... given tank dimensions of 120cm L x 60cm W, I expect that light distribution is quite uneven with significantly shaded areas .... then add in the 60cm depth ...
These figures demonstrate the effect of increasing distance from light source to substrate

Lowering the tiles to just slightly above the water surface would increase PAR but also reduce the area "covered" by the tiles, so this may need some trial & error.
I'd definitely run tiles at 100% - given that CO2 is available.