Juwel Trigon 190 with TMC LEDS

[aquascape1987]

Hi

I wonder if anyone can help me out with this?

My questions centre around how I reasonably accurately can determine whether or not I have enough light/not enough light in my aquarium using TMC LED lights. Obviously the Watts per Gallon rough rule of thumb used for T5s can not be reliably applied, and I have found so much mixed and confusing information regarding calculating the same for LED's on the net.

A bit of background:

Im currently building a scape using the Juwel Trigon 190 and have removed the standard T5 tubes and replaced them with 1 x TMC Grobeam 600 strip LED and 1 x TMC Grobeam 1500 Ultima Colourplus LED tile, both controlled by TMC's 'Smart Control 8' unit. The tile is on the back triangular flap positioned in a diamond configuration. e.g point of square fitting pointing to front of tank. The Grobeam 600 strip in a normal position accross the front flap.

The tank is going to be heavily planted, pressurised FE C02 injection and is filtered by 2 x Fluval G6 filters. One distributing heated water via Hydor inline and the other distributing C02 using an inline diffuser.

I will be EI dosing as well and planting as heavily as I can afford from the get go.

So my questions speciifcally are:

1) Is there a way to accurately calculate the WPG requirement for my tank using these LEDs.?

2) What sort of intensity settings should I be setting for the peak of the photoperiod with the controller (obviously dependant upon the answer to the first question)

All guidance really appreciated.

Richard

 

[alto]

AFAIK TMC is still using Cree LED's which means that you can use CREE to compare lamp details, just confirm with TMC the specifications of both lamps for your manufacture series.

You can try looking at the lamps over the tank in a darkened room - this will give you some measure of light spread, though intensity is very subjective as the human eye perceives some wavelengths much more than others (a higher PAR lamp can actually appear dimmer to the human eye), then place your hardscape & see how that creates shadows ... as tank is 60cm depth, I'd not have the lamps at a considerable distance (obviously PAR at surface will be very different than PAR at substrate level) but when starting a tank, as plants are not actively growing, be conservative with light intensity & duration & generous with the CO2 (which I'd run 24/7 especially if there is considerable ambient light in the room).

Depending on substrate choice & ammonia levels & your daily time available, add algae crew (otocinclus, amano & cherry shrimps) as soon as safely possible - at this stage control CO2 levels

 

[aquascape1987]

The spread of light covers the bottom of the tank well, as I've experimented for a while with the positions. As for distance from the substrate, they are fixed into the standard hood. Is the a PAR per gallon rule or something that can be applied? When I said intensity I meant % as the controller allows u to ramp up and down and set the brightness as a % of full power?

 

[aquascape1987]

Hello,
The concept of good/average/poor PAR values only has meaning in relation to the level of CO2 being injected. If CO2 is being injected that the injection efficiency and the gas distribution will be factors for good/average/poor PAR.
To simplify, and to have a more meaningful use of the PAR values, consider that in general, PAR measured at the substrate level will determine whether the lighting is low, medium or high. That is what wazuck was showing in his chart and I think that is what you should focus on. Once you know whether your lighting is low/medium/high then,as wazuck mentions, you can determine what steps are necessary to have good/average/poor.
If PAR at the substrate level is approximately 50 micromoles or less, this is generally considered low light.
If PAR at the substrate level is between 50-150 micromoles, this is generally considered medium light.
If PAR at the substrate level exceeds 150 micromoles, this is generally considered high light.
Notice that I've only listed measurement at the substrate. This measurement is used as a proxy for the PAR values at other heights above the substrate because the light will roughly follow the inverse square rule. So depending on the height of the tank, the PAR values will increase to some maximum value at the water's surface.
Because most plants grow vertically they are always faced with a variety of PAR values. The leaves at the top of the plant will encounter a higher PAR than the leaves at the bottom of the plant. So it's not really possible to define any one PAR value as being optimal because each leaf must allocate resources to assimilate the light, nutrients and CO2 at their vertical location, which will differ greatly from the conditions at other vertical locations along the stem.
So, if you have a PAR meter and you do not wish to inject CO2, then you know that you should, in general, keep the PAR value at the substrate to less than 50 micromoles, and that will be good or average. If you insisted on using the 150 micromole level then this would be considered poor, because it would be too much and the plants would most likely suffer CO2 deficiency. However, if you then installed a CO2 injection system, and if you installed a good flow/distribution system, then the 150 micromole reading would be considered good/average. If you kept the CO2 system in place and then reduced the substrate PAR value back to 50, then this would still be considered good/average.
Cheers,

Seems the answer may be found in this quote from Ceg above. Cant believe I didnt see this considering I have searched all over the internet and not found anything I felt i could trust so far.

It would seem from this that that I need to know is the PAR at substrate level. Which is tricky without a PAR meter, so all I can go on is the manufacturers PAR values provided.

Does anyone know how I can roughly determine this? My lights are according to TMC, at 400mm high suspension PAR 61 Micromoles for the Grobeam strip and PAR 129 Micromoles for the Grobeam tile.

I think that the answer might be that to do it properly, I need a PAR - Can anyone recommend one?

 

[ian_m]

I need a PAR - Can anyone recommend one?

http://www.ukaps.org/forum/threads/new-cheap-par-meter-with-apogee-sensor.37738/