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DIY COB LED info
- Thread starter naoki
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SubRosa
BS Bulldozer
I'll get you a link to the thread when I get onto the desktop.
Est, the cheapest predrilled heatsink for CXB3590 ($27.30), I know, is the Mechatronics Giga, which I mentioned earlier. If it were the smaller CXB3070, there would be cheaper predrilled options. Here is the link:
https://www.cdiweb.com/ProductDetail/MODULEDGIGA152100BHBG-MechaTronix/574068/pid=468
Cutter Electronics carry Mechatronic, too. But I'm guessing that the shipping could be expensive. The sales rep (Mark) there is helpful. I'll ask him if there is an alternative heatsink for CXB3590.
It should work in passive. Here is a bit of technical details. The capacity of heatsink is rated as thermal resistance. This one has 0.53C/W. Smaller number is better, and this is pretty impressive number (reason for the high price). This means that if the heat generate is 1W, the temperature goes up by 0.53C. With CXB3590 driven at about 50W (700mA for 72V version or 1400mA for 36V version), it releases 24W of heat (using the value calculated here). So the temperature goes up by 24 * 0.53 = 12.8C. This is at the area where you attach COB. If ambient temp is 30C, then it becomes 42.8C. The actual temperature of LED (called junction temperature) is higher, but it should be well below 85C. I haven't measured the temperature of LED, but I touch the heatsink next to the COB, and see if it is too hot, I raise the voltage to drive the fan. So I think this one should work passively, but if it is getting hot, maybe you can attach a fan on the top.
If drilling is possible, you could use self-tapping screw. With a decent drill bit (and a couple of spares), it isn't too bad. If not, one of the leading COB mobs, SupraSPL, uses thermal compound and Kapton Tape as the main way to attach the COB to the heatsink (scroll down to message #332).
Pictures of your DIY lights - Post your pics!!! | Page 17 | Rollitup
It is beyond my comfort zone, but he has been doing it for a long time without problems, and many others follow it. If you go this way, I think you should get the big heat sink from HeatsinkUSA instead of CPU heatsink. There is more space to attach the tape, and it is good to be "semi-passive" in a small chance of fan failure.
Aero, it looks great! Did you use rivets to attach the angle to the heatsink?
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It's true that lower temp influence the longevity and lumen maintenance. With longevity, I have seen some data showing it is a diminishing return. Or I should say that they last long enough below certain temperature of LEDs. I think they use the case temperature, Tc (the temperature you can measure on the access point on the cob) of around 85C, as the standard (they can tolerate much higher temp). The junction temperature (the actual temperature individual LED is experiencing) is higher than this. I haven't measured Tc, but I think that is is less than 60C in our kind of setup (I might be wrong here). So ours should last long enough.
Active cooling is advantageous to reduce the cost (and weight) without sacrificing the efficiency. Indeed, if I can justify paying lots of money for giant heatsink, simplicity of passive cooling is much more appealing (less things to break).
I got parts for water-cooled CXA3070 x 2, but I haven't assembled it yet. I want to put them inside of a relatively small enclosure (for cool-intermediate growing orchids in 75/55F range), and pump out the heat. This relocation of heat is a good advantage for this kind of application. The cost is quite a bit higher, though. We'll see how it goes.
Active cooling is advantageous to reduce the cost (and weight) without sacrificing the efficiency. Indeed, if I can justify paying lots of money for giant heatsink, simplicity of passive cooling is much more appealing (less things to break).
I got parts for water-cooled CXA3070 x 2, but I haven't assembled it yet. I want to put them inside of a relatively small enclosure (for cool-intermediate growing orchids in 75/55F range), and pump out the heat. This relocation of heat is a good advantage for this kind of application. The cost is quite a bit higher, though. We'll see how it goes.
Naoki..yes I riveted the heatsink to the outer rails. I also like the idea of drilling and using self tapping screws. It was a lot of extra work to drill and tap those little screws that hold down the COB holder. I still would rather have the COB in a holder screwed down rather than the Kapton Tape. I know that those screws aren't going anywhere! These should last a very long time why cut corners?
Est, I've been communicating with Matt, and he said that he tested CXB3590 on IceLED Ultra or something similar. The data sheet doesn't specifically say it, but he said there were predrilled holes which matches with 50mm spacing for CXB3590. He was going to confirm this, but I haven't heard back yet (it probably be will be next Mon). He wasn't sure about the model; IceLED Ultra, Xtra Ultra, or Ultra VS (and I'm not sure what are the differences between these models). Here is the link to data sheet.
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Est
Don't know if it would be cost effective or not...if you wanted to order the cpu/fans that I did that are undrilled, and had them sent to me I would be glad to drill and tap them for you. Then for just cost of shipping from me to you you would be all set. Just a thought it would save you paying three times as much for pre-dilled heatsinks. Fans and heatsinks aren't that heavy so shipping shouldn't be to bad.
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Great, I'll keep my eyes open for his followup. Thanks again for making contact on my behalf!
That's an incredibly generous of you! I'm going to see how the above turns out and go from there. I may just take you up on your offer.
I haven't tried them yet but I'm going to on my next build. The 115 angle of view seems to give a nice pattern of light. I'm going to use them on new build to use occasionally to protect them when I foliage spray or spray for pest, to protect the cobs. Then I will remove them for regular use. I also read somewhere that they have found that the lens trap gases given off from the coating on the cobs and diminish there life some? Please take this with a grain of salt as I can't quote said article right now. But it warrants looking into. Maybe Naoki has more input on lens and reflectors.
LEDiL has Angelina line of reflectors which works with CXB3590 or CXB3070. I think it is around $10.
Led lighting - Products | Ledil
With Ideal COB holder, you need 1 extra piece, which connect the LEDiL to the COB holder. For CXB3590, you need 50-2300AN , for CXB3070, you need 50-2100AN. These are about $1.
Chip-Lok® LED Reflector Adaptor
KingBrite recently made a something similar (copy of Ledil F13838_ANGELINA-XW). It is very cheap ($0.80 ea), but the shipping is not, so you'll need to buy quite a few. Again, you can connect to the Ideal COB holder with the adapter I mentioned above.
They also have some glass lens for CXB3590 ($5.60). I don't know the details about this lens, though. So from KingBrite, you can have two options for CXB3590:
Led glass lens: led + Ideal holder 50-2303CR + LED glass lens KB-HB100-80 (diameter 100mm, 80degree).
Led reflector: led + Ideal holder 50-2303CR + Ideal connector 50-2300AN + Reflector KB-D82-90RF (diameter 82mm, 90degree).
As aerogrower mentioned, heat might get trapped, but I have seen that others have used the lens.
Early on, I made DIY reflectors from tin cans (e.g. from chopped tomato) and small yogurt containers. But I'm not using them now. I grow plants in reflective tents, so the light get bounced back somewhat onto the plants (reflection does lose some light, though).
If you reduce the beam angle, the lower leaves get shadowed more. This isn't a big issue with rosette type plants like Drosera. Without the reflector, it can reach to the lower leaves. This is a big advantage for me. Indeed, the main issue of COB is that it is more of point source light, and it's not diffused enough. So I don't want to make highly directional light. In other words, if you have a big grow area, it may make sense to use reflectors around the edge of the grow area, but in the middle, you might not need the reflectors. Or if you have to set up the light really far away, then the narrow beam with reflectors are good.
Led lighting - Products | Ledil
With Ideal COB holder, you need 1 extra piece, which connect the LEDiL to the COB holder. For CXB3590, you need 50-2300AN , for CXB3070, you need 50-2100AN. These are about $1.
Chip-Lok® LED Reflector Adaptor
KingBrite recently made a something similar (copy of Ledil F13838_ANGELINA-XW). It is very cheap ($0.80 ea), but the shipping is not, so you'll need to buy quite a few. Again, you can connect to the Ideal COB holder with the adapter I mentioned above.
They also have some glass lens for CXB3590 ($5.60). I don't know the details about this lens, though. So from KingBrite, you can have two options for CXB3590:
Led glass lens: led + Ideal holder 50-2303CR + LED glass lens KB-HB100-80 (diameter 100mm, 80degree).
Led reflector: led + Ideal holder 50-2303CR + Ideal connector 50-2300AN + Reflector KB-D82-90RF (diameter 82mm, 90degree).
As aerogrower mentioned, heat might get trapped, but I have seen that others have used the lens.
Early on, I made DIY reflectors from tin cans (e.g. from chopped tomato) and small yogurt containers. But I'm not using them now. I grow plants in reflective tents, so the light get bounced back somewhat onto the plants (reflection does lose some light, though).
If you reduce the beam angle, the lower leaves get shadowed more. This isn't a big issue with rosette type plants like Drosera. Without the reflector, it can reach to the lower leaves. This is a big advantage for me. Indeed, the main issue of COB is that it is more of point source light, and it's not diffused enough. So I don't want to make highly directional light. In other words, if you have a big grow area, it may make sense to use reflectors around the edge of the grow area, but in the middle, you might not need the reflectors. Or if you have to set up the light really far away, then the narrow beam with reflectors are good.
I was reading a bit about the Kingbrite lenses last night. It sounds like the light transmittance isn't great on them and I'm not really sure how you'd wire the COB up with the lens on.
Thanks for the information about the Ledil reflectors, it sounds like that might be a better way to go. My main interest in narrowing the beam angle is specifically to be able to raise the light up to grow taller plants than I can right now. I don't really have a good enclosed space to set up reflectors so narrowing the viewing angle of the light source seems like a better option for me.
Is there a particular website you would recommend buying one of these from? Newark and Digikey appear to require orders of 50+ units.
Thanks for the information about the Ledil reflectors, it sounds like that might be a better way to go. My main interest in narrowing the beam angle is specifically to be able to raise the light up to grow taller plants than I can right now. I don't really have a good enclosed space to set up reflectors so narrowing the viewing angle of the light source seems like a better option for me.
Is there a particular website you would recommend buying one of these from? Newark and Digikey appear to require orders of 50+ units.
Currently, I would like to build a single COB grow light to test out and to expand my grow area. I'm trying to decide between the CXB3070 and CXB3590. I would like to cover approximately a 2'x2' area for full sun plants like sundews and for germinating Sarracenia seeds. I'm thinking that I may not purchase a reflector now, since I don't know exactly what angle would be best so I will likely build my own to test.
My current setup is a 2x2' T5HO fixture which produces about 4000 lumens for a 1'x2' area. This seems like about the right amount of light, though I don't have any reflectors set up so I do lose some of it.
So if anyone can offer me some advice: Which one of these COBs would be ideal for my setup and how many watts should I run it at? Which color temperature/bin offers the highest PAR efficiency?
My current setup is a 2x2' T5HO fixture which produces about 4000 lumens for a 1'x2' area. This seems like about the right amount of light, though I don't have any reflectors set up so I do lose some of it.
So if anyone can offer me some advice: Which one of these COBs would be ideal for my setup and how many watts should I run it at? Which color temperature/bin offers the highest PAR efficiency?
If you can have enough room above plants, you can basically use any reflectors with a narrower beam pattern (i.e you can move the light far away to make sure the plants don't get too much light). You could try something like 60-90 degree beam angle, but you can add the reflector later, too. 90 degree means 45-degree in both side, so from 2 feet distance, the circle diameter is around 2 feet.
I would say that try CXB3070. You'll gain a bit more output from CXB3590 (for the same watt), but I'm not sure if it justifies the price difference (unless you are a efficiency-number freak like me).
CXB3070 4000K BD bin (1.4A, 50W, 50C Tj) gives 7989 lumen according to:
Cree Product Characterization Tool
Since it is directional (unlike T5HO), you'll get more than 2x light over your current T5HO setting, so it should cover 2'x2' area. One glitch is that the coverage area is not as even as T5 (high light area in the center).
From my calculation, lowest CRI and higher color temp gives more PAR in general. But in terms of yield photon flux (YPF; i.e. after putting weight representing that red light is more efficient than blue light for photosynthesis (PS)), the lower color temp isn't so far behind (i.e. color temp doesn't matter too much). Higher bin is always better if you can find them.
Here are the relevant values if you want to calculate by yourself.
[Edit: oops, I posted this info in p.2 of this thread. I have forgotten about it, so this is just a subset of the previous table.]
Basically, you can get the lumen (or lumen per watt) for each CRI/K model from the Cree datasheet. Note that higher K generally have higher lumen values (and higher bin numbers). Then you can convert the lumen value to PAR photosynthetic photon flux (PPF; use the multiplier in par.ppf.um) or to YPF (use ypf.per.lum column). The value calculated has the unit of micromol/s. The other 2 columns can be used to convert the foot-candle reading from light meter to PPFD or YPFD (unit will be micromol/m^2/s). PPF"D" and YPF"D" represent "D"ensity. So PPF and YPF are the total output from the fixture, PPFD and YPFD are the density of these light on the leaf (i.e PPF per m^2). This is similar to lumen (total output) vs lux/fc (density).
Now, one thing to note is that PS is not everything. I'm not completely familiar with the physiology of CP, but red light is likely to be important for phytochrome related phenomena. I'm guessing that day length influences the seed and plant dormancy of Saracenia. So red and far red ratio becomes relevant. I have been using 3000, 4000, and 5000K, and all seems to work well for orchids. I subjectively (i.e. without strong scientific support) choose that 4000K is the default for me (it just seems to be a good balance).
Something like this:
Cutter Electronics, Supplier of lowest cost leds on the internet
I think that their coupon is still effective (I think I posted earlier in this thread), but you need to see if it is cheaper domestically once you consider the shipping cost. cutter seems to have top bin frequently, which is difficult to get domestically.
With regard to the driving current, you'll probably need at least 1400mA (50W) if you want to get that much of light from 1x COB. Maybe LPC-60-1400 is a choice: LPC-60 datasheet
If you want to get more light (sacrifice a bit of efficiency) you can go with LPC-100-1750: LPC-100 datasheet
It gives 1750mA (63W), and you'll get 9599 lumen.
These drivers are not dimmable nor highest efficiency, but they are cheap (and good quality).
If you want to go dimmable (1.17-1.95A = 40-70W), HLG-80H-42 is one of the best: HLG-80H datasheet
I personally would go with the cheaper LPC for a single driver + single COB, though. If you are going to connect multiple COB LEDs to a single driver then HLG could be a good choice.
I would say that try CXB3070. You'll gain a bit more output from CXB3590 (for the same watt), but I'm not sure if it justifies the price difference (unless you are a efficiency-number freak like me).
CXB3070 4000K BD bin (1.4A, 50W, 50C Tj) gives 7989 lumen according to:
Cree Product Characterization Tool
Since it is directional (unlike T5HO), you'll get more than 2x light over your current T5HO setting, so it should cover 2'x2' area. One glitch is that the coverage area is not as even as T5 (high light area in the center).
From my calculation, lowest CRI and higher color temp gives more PAR in general. But in terms of yield photon flux (YPF; i.e. after putting weight representing that red light is more efficient than blue light for photosynthesis (PS)), the lower color temp isn't so far behind (i.e. color temp doesn't matter too much). Higher bin is always better if you can find them.
Here are the relevant values if you want to calculate by yourself.
Code:
## ppf.per.lum ppfd.per.fc ypf.per.lum ypfd.per.fc
## Cree.3000K.80CRI 0.01424752 0.1533591 0.01288196 0.1386603
## Cree.3000K.90CRI 0.01407376 0.1514886 0.01230506 0.1324506
## Cree.4000K.80CRI 0.01407376 0.1514886 0.01230506 0.1324506
## Cree.5000K.70CRI 0.01382456 0.1488064 0.01204868 0.1296909Basically, you can get the lumen (or lumen per watt) for each CRI/K model from the Cree datasheet. Note that higher K generally have higher lumen values (and higher bin numbers). Then you can convert the lumen value to PAR photosynthetic photon flux (PPF; use the multiplier in par.ppf.um) or to YPF (use ypf.per.lum column). The value calculated has the unit of micromol/s. The other 2 columns can be used to convert the foot-candle reading from light meter to PPFD or YPFD (unit will be micromol/m^2/s). PPF"D" and YPF"D" represent "D"ensity. So PPF and YPF are the total output from the fixture, PPFD and YPFD are the density of these light on the leaf (i.e PPF per m^2). This is similar to lumen (total output) vs lux/fc (density).
Now, one thing to note is that PS is not everything. I'm not completely familiar with the physiology of CP, but red light is likely to be important for phytochrome related phenomena. I'm guessing that day length influences the seed and plant dormancy of Saracenia. So red and far red ratio becomes relevant. I have been using 3000, 4000, and 5000K, and all seems to work well for orchids. I subjectively (i.e. without strong scientific support) choose that 4000K is the default for me (it just seems to be a good balance).
Something like this:
Cutter Electronics, Supplier of lowest cost leds on the internet
I think that their coupon is still effective (I think I posted earlier in this thread), but you need to see if it is cheaper domestically once you consider the shipping cost. cutter seems to have top bin frequently, which is difficult to get domestically.
With regard to the driving current, you'll probably need at least 1400mA (50W) if you want to get that much of light from 1x COB. Maybe LPC-60-1400 is a choice: LPC-60 datasheet
If you want to get more light (sacrifice a bit of efficiency) you can go with LPC-100-1750: LPC-100 datasheet
It gives 1750mA (63W), and you'll get 9599 lumen.
These drivers are not dimmable nor highest efficiency, but they are cheap (and good quality).
If you want to go dimmable (1.17-1.95A = 40-70W), HLG-80H-42 is one of the best: HLG-80H datasheet
I personally would go with the cheaper LPC for a single driver + single COB, though. If you are going to connect multiple COB LEDs to a single driver then HLG could be a good choice.
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Thank you very much naoki. It certainly is a lot of information to take in for someone as new to LED lighting as I am but this gets me one step closer to taking the plunge.
Two more quick questions:
I've noticed that people seem to stick with <5000K lighting for LEDs, yet bulbs as high as 6500k are common with fluorescent lighting. Why is that?
What does Cree's two-step, three-step, and five-step binning mean? They have multiple "steps" for some color temperature/bin combinations but don't understand the chart at the end of the spec sheet about it.
Two more quick questions:
I've noticed that people seem to stick with <5000K lighting for LEDs, yet bulbs as high as 6500k are common with fluorescent lighting. Why is that?
What does Cree's two-step, three-step, and five-step binning mean? They have multiple "steps" for some color temperature/bin combinations but don't understand the chart at the end of the spec sheet about it.
LED stuff is a bit complicated, and it did take quite a bit to learn about it for me, too. Sorry if I don't explain things in an easy way... I'm trying to leave out too much details, but I frequently end up with difficult explanation...
My theory is that people took "day light" spectrum of fluorescent light literally. Here is my measurement of T5HO:
3000K 82 533 1-2mo old, Philips F54T5/830
4100K 83 590 new F54TH/841/HO/ALTO
5000K 80 620 1-2 mo old, F54T5/850
5000K 85 625 new F54T5/850/HO/ALTO
The measurement is taken at 12" from the tube in a typical fixture/reflector with Li-COR LI-190 (for PPFD) and LX1330B (fc).
2nd column is PPFD in micromol/m^2/s
3rd column is fc.
There is a bigger difference in terms of foot-candle (which isn't as relevant as PPFD), and higher K seems to have higher fc. But in terms of the PPFD, the difference is pretty small. I didn't have 6500K, but the trend should be similar. I used to use whatever available between 3000-6500K for T5HO. Those purple plant bulbs do indeed have higher efficiency than white ones in my measurement (link to my measurement), but it is questionable if the extra cost is worth spending (since the output decays in 1-2 years).
As a related note, I got some data comparing PAR efficiency of T5HO (T8 and LED, too). Here is a calculation done by some planted aquarium people from South Africa to find best T5HO bulbs. It is sorted from the most efficient to less efficient (the top is the best). Basically they digitized the emission spectra, and calculated how much plant relevant light is emitted for a given amount of electric power usage. This is the "PAR efficiency" column (micomol/J is the unit). K (kelvin) column is the calculated (not the advertised) corrected color temp. This is a bit old data, so I'm not sure if all of these are still available. To be honest, I'm not sure if the PAR efficiency of the top one is really correct. It seems to be too high for fluorescent light. Top rated ones seem to have higher K values, so there may be some reasons why people use 6500K. But this is from calculation (not measurement). Also, some of the specialty bulbs may have quite different emission spectra from the typical T5HO.
The other factor is the emitted spectrum of fluorescent bulbs (jagged shape with a few major peaks corresponding to different phosphors) is very different from LED (smooth, 1 blue peak + yellow/red peak from phosphor). Once you start to go above 5000K with LED, the light is dominated by the blue peak, which doesn't look too good for phytochrome related response (my guess here). Many MJ people goes with 3000-4000K COB LEDs for flowering because their flowering is photoperiodic (phytochrome is relevant for this process) and requires red light.
Note that typical spectral power distribution (SPD) curve which is in data sheet has power (watt) on y-axis. But the photosynthesis is more related to the number of photons than power, so you need to correct the y-axis. 1 blue photon has more energy than 1 red photon. So if you cover y-axis to number of photons, the blue peak becomes a bit smaller.
Those are the color accuracy. For some applications, they requires that color of one light to match with another. I forgot, but I think 2-step is more accurate than 5-step. But for plants, accurate color match isn't relevant. So I ignore that part of binning. So I go with whatever the cheaper ones with lowest CRI and highest luminous flux bin. So for example, you can look at p.3-4 of the cxb3070 datasheet. For 4000K/CRI70, you have BB or BD bins (they call it minimum flux "group", but this is the bin number which most of us are talking about). BD bin is the best, and the product number is CXB3070-0000-000N0BBD40E. This is the top bin for 4000K (the link to Cutter above is this one), and I haven't seen it available from other vendors. Now if you go to 4000K/CRI80, then the top bin is BB (which is lower than BD). There are 2-step and 4-step version, but I would go with either one (probably the cheaper one) if there is a choice. You can think that a higher CRI requires more phosphor, and more phosphor could result in a bit of light loss during the conversion of blue light to yellow/red light. Generally, if you go down in K, the top bin class becomes lower (e.g. for 3000K, AD is the top bin). So you have to look at the data sheet to decide what is the top bin of each category.
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Well I finally took the plunge and assembled 2 COB lights. It took a lot more time than I was expecting, but they seem to be working just as well as I'd hoped. I set up one indoors to expand my tropical grow area, and the second one out in the garage so I can start collecting winter-growing sundews as well as providing more light for over-wintering outdoor plants that are not tolerant of freezes.
For the build, I used the parts recommended to me (CXB3070 4000K 70CRI + 1400mA driver) and some old computer CPU heatsinks I had lying around. I reused some old 5V AC adapters, extending the cord with twisted pair wire out of CAT-5 network cabling for the fans, and used 16 gauge appliance wire to extend the driver cord. The 16 gauge is a bit big for the connectors on the LED holders, so I'm going to make sure I shape the wire to fit the holder BEFORE tinning it next time. I wrapped some thin copper wire around the fan mount on the heatsinks to serve as a hanger, and used some thin rubber tubing to attach that to a mounting point above.
I'm very happy with the results, and the light seems even brighter than I expected. Comparing one of these (which should be producing somewhere around 8000 lumens) to my T5 fixture (4000 lumens) it seems to be significantly brighter, despite covering double the area. The coverage isn't as uniform as I'd like and there's still a lot of waste light to the sides so I'm planning on adding some sort of reflector and raising the lights higher though I'm still investigating the best way to go about that. I would have ordered a commercial reflector with the COBs but wasn't sure what angle would be best when I ordered. I've been thinking that those domed plastic lids they put on things like smoothie cups would be perfect when lined with foil, but I don't have any on hand.
I am aware that my Roridula looks terrible. I found out the hard way that letting the leaves stay wet for an extended period of time is very bad and ended up cutting off the growth point due to a severe botrytis infection. It has several new growth points emerging though so it's well on the road to recovery.
For the build, I used the parts recommended to me (CXB3070 4000K 70CRI + 1400mA driver) and some old computer CPU heatsinks I had lying around. I reused some old 5V AC adapters, extending the cord with twisted pair wire out of CAT-5 network cabling for the fans, and used 16 gauge appliance wire to extend the driver cord. The 16 gauge is a bit big for the connectors on the LED holders, so I'm going to make sure I shape the wire to fit the holder BEFORE tinning it next time. I wrapped some thin copper wire around the fan mount on the heatsinks to serve as a hanger, and used some thin rubber tubing to attach that to a mounting point above.
I'm very happy with the results, and the light seems even brighter than I expected. Comparing one of these (which should be producing somewhere around 8000 lumens) to my T5 fixture (4000 lumens) it seems to be significantly brighter, despite covering double the area. The coverage isn't as uniform as I'd like and there's still a lot of waste light to the sides so I'm planning on adding some sort of reflector and raising the lights higher though I'm still investigating the best way to go about that. I would have ordered a commercial reflector with the COBs but wasn't sure what angle would be best when I ordered. I've been thinking that those domed plastic lids they put on things like smoothie cups would be perfect when lined with foil, but I don't have any on hand.
I am aware that my Roridula looks terrible. I found out the hard way that letting the leaves stay wet for an extended period of time is very bad and ended up cutting off the growth point due to a severe botrytis infection. It has several new growth points emerging though so it's well on the road to recovery.
