I started my reef journey many moons ago when keeping softies was considered an accomplishment. Over the years I have been amazed by the advances and technology that has become available to us. It is really incredible how far we have come in this hobby.
By nature I am a techno-geek and eye candy junky. My two hobbies ( Reefing and Astrophotography) satisfy my never ending fascination with gadgets, technology, science, and the beauty of nature. As such I am guilty of being an early adopter of new products and technology.
In terms of lighting, I was a very early adopter of LED lighting for Reef aquaria. My first LED was the original Solaris for anyone that remembers that fixture. It worked well and yes it convinced me that one could grow corals with LED's. Over the years I was forced to return to MH/T5 combos as the Solaris died and the company with it.
Later on, I played with the nano-tuner LED for a fluval edge that I turned into a Pico reef, the AI nano and subsequently Vega. More Recently I moved on to the Radion G4. I have always preferred the lack of heat and the greater control of LED's but honestly the shadowing and peculiar growth patterns of my corals always bothered me.
I am in the process of a new build- a reefer 425xl and planned on using my Radion G4 Pros. When I heard of the Aquatic-Life "T5/bring your own LED" hybrid fixture, my interest was immediately perked. Although this fixture does the job it is simply to utilitarian for my tastes and I was not impressed with the fit and finish and the average reflectors.
Enter the Giesemann Stellar.....
I first encountered news of this fixture on reef builders and thought to myself "ahh finally! someone will make a high quality hybrid." I had experience with Giesemann in the past having used their T5 fixtures and really looked forward to this being a possible solution for my needs. Giesemann is known for well constructed high quality products and I had no doubts this would be the quality answer for a hybrid fixture with the flexibility of using your desired LED. Further it appeared to be based on their Gemini fixture which I find to be visually appealing, sleek and well constructed.
I searched for a date that it would be available in the US and stumbled upon the fact that I could order directly from them. I went ahead and pulled the trigger and ordered the 900mm iridium version that will house 4 x 39 watt T5 bulbs and the LED of your choice. The space available for the LED's using the standard bracket is 10 inches which is more than ample for my Radions.
I received an email that they would be making a 110v version for me and that it would ship in a couple weeks. I also ordered the optional shortening end brackets that take the fixture from 575mm front to back down to 500mm. I thought this would be a better fit for my tank (turns out the standard works well for the XL version of reefer, however if you have a 250, 350, 450, you will need the shortening brackets or the fixture will extend beyond the width of the aquarium).
Several weeks later shipping was confirmed and the product arrived Fedex in good condition. It was well packaged and protected and suffered no damage in transit. My initial impression was excellent, the finish was a nice dark (not black but gray like) powder coated finish. The classic Giesemann logo on the end, and the build solid and sturdy. The fixture comes unassembled with two T5 housings which contain high quality reflectors and an acrylic shield already completed. Two standard end brackets, LED brackets, a bag of screws and nuts, and some fairly rudimentary instructions.
I placed the two T5 housings on the floor and lined them up, I attached the side brackets (the shorter version I had ordered extra) and used the supplied screws. There are two sizes of screws to be aware of ( this is not mentioned in the instructions so be careful). Two thiner screws which go on the front and back ends of the brackets, and two fatter screws for the middle two holes. The thinner screw heads are quite small and fragile, the pilot holes are not tapped so be careful as it is very easy to strip the heads. I almost stripped one of mine.
With this completed, you can insert the LED brackets into the groove on the inside surfaced of the housings. You can do this before attaching the end brackets but it doesn't matter as they angle out. The LED brackets have an adhesive tape which will help lock your LED's in place. I would have preferred a more sturdy method but this works. I also purchased the hanging kit which comes without instructions but is similar to others on the market.
Next I went to insert my T5 bulbs and encountered the first shortcoming of the fixture. Unlike the Gemini housing that has a notch on the end allowing for sliding out of the acrylic shield, the Stellar does NOT. Why?? I have no idea as it makes no sense not to include it. I can only surmise that this was an oversight in their design of the fixture. I emailed Giesemann regarding this. I received no response so after a couple days I emailed another person at their company and was told they would get back to me. The response was not what I wanted to hear. Basically I was told to just loosen the screws securing one of the end brackets, angle it and pull out the acrylic shield.
Here is their response:
"no the end plates do not have a notch. To replace the T5 lamps later and to remove the acrylic shield you can loosen the outer screw and flip the profile slightly.
This allows you to remove the acrylic shield without unmounting the whole end plate."
I had already tried that and although possible, it is quite cumbersome. I can only imagine when I have the fixture hung that this will be even more difficult. Further, each time you loosen those screws on the ends, the heads are in danger of becoming further stripped. Not optimal to say the least. I have emailed them back twice asking if the Gemini fixture end brackets will work on the Stellar (since they have the notch) but I have not yet received a response.
Well I finally managed to remove the acrylic shield and put in my bulbs. I fired up the fixture and the lights come right on without any glitch or issue. I let them burn in for a couple hours to test the fixture and start putting some age on these new bulbs. The light is uniform, the bulbs burn well and the reflectors are excellent.
I then noticed another issue. There was a lot of heat building up and I became aware that the shortening brackets do not have ventilation slits! The standard 575mm bracket does have several slits on the end but not these 500mm shortening ones. Why?? again I have to conclude it was an oversight in their design.
I included a question regarding this in my previous email to them. They responded:
"the longer version has this ventilation slits because you can put there bigger LED units with much more power. But in the shortened version you don’t need them! The shortened version has no ventilation slits – it will be not too hot there is no risk."
I'm not really sure what that means. The end bracket width has nothing to do with the type of LED. My G4 Radions fit regardless of the bracket I use. These slits are to allow heat from the T5's to dissipate. Clearly they missed something here. I was concerned enough that I removed the shorter brackets and used the standard ones with the ventilation slits. Luckily my tank is the 425XL so the extra front-back width still works. It is basically the same as the tank-
The brackets do have cut outs for cord management and both T5 power cords come out on the same side.
Overall as you can see in the photos, the fixture is well finished and good quality. The shortfalls in the design that I mention are a concern. I am a little disappointed as this is not what I have come to expect from Giesemann. I can understand some oversights but their slow response to my inquiries is not what I have come to expect from them. I have an email pending a response pointing out these issues. I can deal with the longer standard brackets. Money wasted on my part for the shorter brackets that are not useable without ventilation slits in my opinion ( I know others will disagree). However I would really prefer a bracket that allow removal of the acrylic shield for bulb changes such as the Gemini endplate. I am still waiting for a response to this question...
Conclusions:
Overall a nice hybrid fixture that will allow you to use a myriad of LED's on the market. Finish and appearance are sleek and top notch. Reflectors are of high quality as expected of Giesemann products. Aforementioned design flaws notwithstanding, it is a solid contender to the aquatic life fixture but given the cost difference some may not find the difference in quality worth it.
UPDATE:
So I received a follow up email from Giesemann. Basically they are sticking to there guns. They stated that the original design was based on the shorter brackets without ventilation slits. They state that they did extensive thermal testing and that there is no problem. The longer end brackets have slits in the event that the "larger" LED's will somehow transmit heat to the T5's hence the need for ventilation.
Exact quote:
"About the different endplates for STELLAR / GEMINI: The stellar came into the market only in the narrow version first. From the beginning the STELLAR endplates where designed without slots, as we made thermal tests with the T-5´s and there was no need for additional slots. If you look at other products from competitors, they have as well no slots on their endplates. The profile of the Stellar / Gemini is made of thick aluminium and the T-5 ballast is mounted flat on the coolest place inside the profile. In a second step we have designed the wider version of the Stellar-plates to allow more flexibility with larger and stronger LED systems. These wider endplates have additional slots because of the risk that stronger LED lights may produce more heat."
Take it for what its worth. I am not going to dispute their "thermal tests" One point however, the competitor they mention I assume is the Aquatic life fixture (I know of no other at present), That fixture has not acrylic shield so the T5's are not enclosed.
In any event there you have it. I will luckily be able to use the longer ventilated brackets in my case but for those with narrower aquaria be forewarned.
In regards to accessing the bulb compartment for bulb changes- again no slit for sliding out of the acrylic shield. Royal PIA to loosen the endplate, further strip the screw heads and angle the bracket while you bend the shield out!
By nature I am a techno-geek and eye candy junky. My two hobbies ( Reefing and Astrophotography) satisfy my never ending fascination with gadgets, technology, science, and the beauty of nature. As such I am guilty of being an early adopter of new products and technology.
In terms of lighting, I was a very early adopter of LED lighting for Reef aquaria. My first LED was the original Solaris for anyone that remembers that fixture. It worked well and yes it convinced me that one could grow corals with LED's. Over the years I was forced to return to MH/T5 combos as the Solaris died and the company with it.
Later on, I played with the nano-tuner LED for a fluval edge that I turned into a Pico reef, the AI nano and subsequently Vega. More Recently I moved on to the Radion G4. I have always preferred the lack of heat and the greater control of LED's but honestly the shadowing and peculiar growth patterns of my corals always bothered me.
I am in the process of a new build- a reefer 425xl and planned on using my Radion G4 Pros. When I heard of the Aquatic-Life "T5/bring your own LED" hybrid fixture, my interest was immediately perked. Although this fixture does the job it is simply to utilitarian for my tastes and I was not impressed with the fit and finish and the average reflectors.
Enter the Giesemann Stellar.....
I first encountered news of this fixture on reef builders and thought to myself "ahh finally! someone will make a high quality hybrid." I had experience with Giesemann in the past having used their T5 fixtures and really looked forward to this being a possible solution for my needs. Giesemann is known for well constructed high quality products and I had no doubts this would be the quality answer for a hybrid fixture with the flexibility of using your desired LED. Further it appeared to be based on their Gemini fixture which I find to be visually appealing, sleek and well constructed.
I searched for a date that it would be available in the US and stumbled upon the fact that I could order directly from them. I went ahead and pulled the trigger and ordered the 900mm iridium version that will house 4 x 39 watt T5 bulbs and the LED of your choice. The space available for the LED's using the standard bracket is 10 inches which is more than ample for my Radions.
I received an email that they would be making a 110v version for me and that it would ship in a couple weeks. I also ordered the optional shortening end brackets that take the fixture from 575mm front to back down to 500mm. I thought this would be a better fit for my tank (turns out the standard works well for the XL version of reefer, however if you have a 250, 350, 450, you will need the shortening brackets or the fixture will extend beyond the width of the aquarium).
Several weeks later shipping was confirmed and the product arrived Fedex in good condition. It was well packaged and protected and suffered no damage in transit. My initial impression was excellent, the finish was a nice dark (not black but gray like) powder coated finish. The classic Giesemann logo on the end, and the build solid and sturdy. The fixture comes unassembled with two T5 housings which contain high quality reflectors and an acrylic shield already completed. Two standard end brackets, LED brackets, a bag of screws and nuts, and some fairly rudimentary instructions.
I placed the two T5 housings on the floor and lined them up, I attached the side brackets (the shorter version I had ordered extra) and used the supplied screws. There are two sizes of screws to be aware of ( this is not mentioned in the instructions so be careful). Two thiner screws which go on the front and back ends of the brackets, and two fatter screws for the middle two holes. The thinner screw heads are quite small and fragile, the pilot holes are not tapped so be careful as it is very easy to strip the heads. I almost stripped one of mine.
With this completed, you can insert the LED brackets into the groove on the inside surfaced of the housings. You can do this before attaching the end brackets but it doesn't matter as they angle out. The LED brackets have an adhesive tape which will help lock your LED's in place. I would have preferred a more sturdy method but this works. I also purchased the hanging kit which comes without instructions but is similar to others on the market.
Next I went to insert my T5 bulbs and encountered the first shortcoming of the fixture. Unlike the Gemini housing that has a notch on the end allowing for sliding out of the acrylic shield, the Stellar does NOT. Why?? I have no idea as it makes no sense not to include it. I can only surmise that this was an oversight in their design of the fixture. I emailed Giesemann regarding this. I received no response so after a couple days I emailed another person at their company and was told they would get back to me. The response was not what I wanted to hear. Basically I was told to just loosen the screws securing one of the end brackets, angle it and pull out the acrylic shield.
Here is their response:
"no the end plates do not have a notch. To replace the T5 lamps later and to remove the acrylic shield you can loosen the outer screw and flip the profile slightly.
This allows you to remove the acrylic shield without unmounting the whole end plate."
I had already tried that and although possible, it is quite cumbersome. I can only imagine when I have the fixture hung that this will be even more difficult. Further, each time you loosen those screws on the ends, the heads are in danger of becoming further stripped. Not optimal to say the least. I have emailed them back twice asking if the Gemini fixture end brackets will work on the Stellar (since they have the notch) but I have not yet received a response.
Well I finally managed to remove the acrylic shield and put in my bulbs. I fired up the fixture and the lights come right on without any glitch or issue. I let them burn in for a couple hours to test the fixture and start putting some age on these new bulbs. The light is uniform, the bulbs burn well and the reflectors are excellent.
I then noticed another issue. There was a lot of heat building up and I became aware that the shortening brackets do not have ventilation slits! The standard 575mm bracket does have several slits on the end but not these 500mm shortening ones. Why?? again I have to conclude it was an oversight in their design.
I included a question regarding this in my previous email to them. They responded:
"the longer version has this ventilation slits because you can put there bigger LED units with much more power. But in the shortened version you don’t need them! The shortened version has no ventilation slits – it will be not too hot there is no risk."
I'm not really sure what that means. The end bracket width has nothing to do with the type of LED. My G4 Radions fit regardless of the bracket I use. These slits are to allow heat from the T5's to dissipate. Clearly they missed something here. I was concerned enough that I removed the shorter brackets and used the standard ones with the ventilation slits. Luckily my tank is the 425XL so the extra front-back width still works. It is basically the same as the tank-
The brackets do have cut outs for cord management and both T5 power cords come out on the same side.
Overall as you can see in the photos, the fixture is well finished and good quality. The shortfalls in the design that I mention are a concern. I am a little disappointed as this is not what I have come to expect from Giesemann. I can understand some oversights but their slow response to my inquiries is not what I have come to expect from them. I have an email pending a response pointing out these issues. I can deal with the longer standard brackets. Money wasted on my part for the shorter brackets that are not useable without ventilation slits in my opinion ( I know others will disagree). However I would really prefer a bracket that allow removal of the acrylic shield for bulb changes such as the Gemini endplate. I am still waiting for a response to this question...
Conclusions:
Overall a nice hybrid fixture that will allow you to use a myriad of LED's on the market. Finish and appearance are sleek and top notch. Reflectors are of high quality as expected of Giesemann products. Aforementioned design flaws notwithstanding, it is a solid contender to the aquatic life fixture but given the cost difference some may not find the difference in quality worth it.
UPDATE:
So I received a follow up email from Giesemann. Basically they are sticking to there guns. They stated that the original design was based on the shorter brackets without ventilation slits. They state that they did extensive thermal testing and that there is no problem. The longer end brackets have slits in the event that the "larger" LED's will somehow transmit heat to the T5's hence the need for ventilation.
Exact quote:
"About the different endplates for STELLAR / GEMINI: The stellar came into the market only in the narrow version first. From the beginning the STELLAR endplates where designed without slots, as we made thermal tests with the T-5´s and there was no need for additional slots. If you look at other products from competitors, they have as well no slots on their endplates. The profile of the Stellar / Gemini is made of thick aluminium and the T-5 ballast is mounted flat on the coolest place inside the profile. In a second step we have designed the wider version of the Stellar-plates to allow more flexibility with larger and stronger LED systems. These wider endplates have additional slots because of the risk that stronger LED lights may produce more heat."
Take it for what its worth. I am not going to dispute their "thermal tests" One point however, the competitor they mention I assume is the Aquatic life fixture (I know of no other at present), That fixture has not acrylic shield so the T5's are not enclosed.
In any event there you have it. I will luckily be able to use the longer ventilated brackets in my case but for those with narrower aquaria be forewarned.
In regards to accessing the bulb compartment for bulb changes- again no slit for sliding out of the acrylic shield. Royal PIA to loosen the endplate, further strip the screw heads and angle the bracket while you bend the shield out!
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