greying_mantis
New Member
greetings, etc 🙂 apologies in advance, I am including as much info as possible so this is long.
I have a 266ish litre Rena tank. I do not know the model name/number. External dimensions in cm 40d x 70h x 120l. It still has the original light bar with two T8 tubes. The light bar sits within the top rim of the tank, in slots formed in the first inner ledge of the rim. The lid is a flat sheet of metal that sits flush with the top of the rim (I plan to replace this with something transparent). The top rim itself is metal with two internal ledges, 8.5cm deep and completely hides the light bar. The tank has a single metal brace across the middle of the rim. The first internal ledge is approx 2cm from the top (this is the ledge the light bar sits on/in) and the second is just over 4cm below that, level with the brace just above the water.
It’s a low tech tank with no CO2. At the moment we have two 40w T8 tubes that are several years old. Enough to see fish, not enough for much else. Even the java ferns have all-but given up. I know PAR isn’t the be-all-and-end-all of lighting but the calculator on this site suggests I am getting 9-10 at the substrate. The bulbs and/or their starters are failing so instead of getting more of the same I’m looking at other options.
The minimum requirement/motivation for change is sufficient light for a lot of low tech, easy plants. I just want the tank lush again, I’m not trying to grow anything fussy. After that, the considerations are budget (£250 max) and hiding the light source somehow. Enhancing colour is a nice-to-have. “Smart” functionality is not necessary (current lights are on a socket timer - this is fine). Minimum bodging/DIY is needed. A bit of drilling and some cable ties would be fine, but that’s the limit.
I would also like to grow houseplants hydroponically which means either the tank lights doing double duty or a second set of lights somewhere. Ideally the former - I envisage a transparent lid with “ports” for the plants and enough diffused light coming up from the tank to support them. This is also a nice-to-have, not essential.
The ideal would be an LED bar that sits in the same brackets (or at least on one of the rim ledges) under the lid and, like the current T8 bar, is totally hidden from external view, even with a transparent lid. I really struggle with visible light sources due to migraines - all light in our house is diffused - and the tank is right next to our sofa which means any light source will be above me when sat. If an LED bar within the rim isn’t feasible, then the light needs to be pointed away from the room somehow, or have some sort of shade.
I do worry about trying to put LEDs under the lid as this may not give enough heat dissipation and a lot of units I have seen are not particularly water resistant. The current light bar is perpetually wet (though not touching the water surface). Similarly, attaching lights to the underside of the lid would seem to compromise the heat sink capability of the units - they mostly seem designed to sit above a clear lid or open tank. The current lid sits very, very close to the top of the current light bar. There needs to be a lid of some sort as we have fish that jump, cats and birds (feather dust and seed get everywhere)
I’ve looked at T8 retrofit LEDs but the ones I have found seem too wide for our light bar (the tubes sit either side of the bar and very close to it), don’t come in the length we need (our tubes are 107cm/42”) not actually designed for existing T8 fittings or have insufficient IP ratings.
I’ve seen submersible units. Hygger and other budget brands have inexpensive submersibles - are they truly safe? Does anyone have experience with them? At 24W (for the Hygger version) I suspect I will need more than one? It’d need to be placed on the inner front glass facing away from the room which would get very ugly if I had more than one. Or maybe cable tied to the underside of the brace bar which will really get in the way for tank maintenance. I don’t think I am up to making a custom mount to sit on the rim ledges, and attaching it to the lid also seems deeply inconvenient (especially as I hope to change the lid for 2+ clear panels).
The other option I am considering is the Twinstar G line as they are very shallow and designed to sit under a hood. The Twinstars could sit on either the top or bottom ledge of the rim. If the bottom, would the Twinstars be OK if the LED side contacted the centre brace of the tank? If the top, would the heat dissipation against the flat lid be an issue? What if the metal lid was replaced with a suitable plastic - reduced heat sinking I assume, and might deform the plastic? I don’t have a good sense of how hot these units get. I can also only afford one Twinstar G (the 120G) though could potentially save up for a second in the future. Would one be OK for the aforementioned easy plants? Should I be concerned about the lack of white LEDs? I also can’t seem to find G+ for online sale in the UK so this doesn’t seem a viable upgrade over the G.
Edit to add - I know outdoor floodlights are an inexpensive way to get good aquarium lighting but given the restrictions I have around DIY, needing a lid and visible light sources, I’m not sure I could make this work. But I am open to the suggestion if anyone can help me envisage how I could mount them. I can make a mount bar out of wood but that seems like a recipe for mold!
I realise this is a very specific request with a lot of inbuilt obstacles, so I’m mostly hoping someone has dealt with this tank or similar and has some insight. Or is a complete tech nerd with an encyclopaedic knowledge of the lighting market 😂
Thanks in advance!
(p.s. I know the poor tank is going through an ugly phase, please be kind)
I have a 266ish litre Rena tank. I do not know the model name/number. External dimensions in cm 40d x 70h x 120l. It still has the original light bar with two T8 tubes. The light bar sits within the top rim of the tank, in slots formed in the first inner ledge of the rim. The lid is a flat sheet of metal that sits flush with the top of the rim (I plan to replace this with something transparent). The top rim itself is metal with two internal ledges, 8.5cm deep and completely hides the light bar. The tank has a single metal brace across the middle of the rim. The first internal ledge is approx 2cm from the top (this is the ledge the light bar sits on/in) and the second is just over 4cm below that, level with the brace just above the water.
It’s a low tech tank with no CO2. At the moment we have two 40w T8 tubes that are several years old. Enough to see fish, not enough for much else. Even the java ferns have all-but given up. I know PAR isn’t the be-all-and-end-all of lighting but the calculator on this site suggests I am getting 9-10 at the substrate. The bulbs and/or their starters are failing so instead of getting more of the same I’m looking at other options.
The minimum requirement/motivation for change is sufficient light for a lot of low tech, easy plants. I just want the tank lush again, I’m not trying to grow anything fussy. After that, the considerations are budget (£250 max) and hiding the light source somehow. Enhancing colour is a nice-to-have. “Smart” functionality is not necessary (current lights are on a socket timer - this is fine). Minimum bodging/DIY is needed. A bit of drilling and some cable ties would be fine, but that’s the limit.
I would also like to grow houseplants hydroponically which means either the tank lights doing double duty or a second set of lights somewhere. Ideally the former - I envisage a transparent lid with “ports” for the plants and enough diffused light coming up from the tank to support them. This is also a nice-to-have, not essential.
The ideal would be an LED bar that sits in the same brackets (or at least on one of the rim ledges) under the lid and, like the current T8 bar, is totally hidden from external view, even with a transparent lid. I really struggle with visible light sources due to migraines - all light in our house is diffused - and the tank is right next to our sofa which means any light source will be above me when sat. If an LED bar within the rim isn’t feasible, then the light needs to be pointed away from the room somehow, or have some sort of shade.
I do worry about trying to put LEDs under the lid as this may not give enough heat dissipation and a lot of units I have seen are not particularly water resistant. The current light bar is perpetually wet (though not touching the water surface). Similarly, attaching lights to the underside of the lid would seem to compromise the heat sink capability of the units - they mostly seem designed to sit above a clear lid or open tank. The current lid sits very, very close to the top of the current light bar. There needs to be a lid of some sort as we have fish that jump, cats and birds (feather dust and seed get everywhere)
I’ve looked at T8 retrofit LEDs but the ones I have found seem too wide for our light bar (the tubes sit either side of the bar and very close to it), don’t come in the length we need (our tubes are 107cm/42”) not actually designed for existing T8 fittings or have insufficient IP ratings.
I’ve seen submersible units. Hygger and other budget brands have inexpensive submersibles - are they truly safe? Does anyone have experience with them? At 24W (for the Hygger version) I suspect I will need more than one? It’d need to be placed on the inner front glass facing away from the room which would get very ugly if I had more than one. Or maybe cable tied to the underside of the brace bar which will really get in the way for tank maintenance. I don’t think I am up to making a custom mount to sit on the rim ledges, and attaching it to the lid also seems deeply inconvenient (especially as I hope to change the lid for 2+ clear panels).
The other option I am considering is the Twinstar G line as they are very shallow and designed to sit under a hood. The Twinstars could sit on either the top or bottom ledge of the rim. If the bottom, would the Twinstars be OK if the LED side contacted the centre brace of the tank? If the top, would the heat dissipation against the flat lid be an issue? What if the metal lid was replaced with a suitable plastic - reduced heat sinking I assume, and might deform the plastic? I don’t have a good sense of how hot these units get. I can also only afford one Twinstar G (the 120G) though could potentially save up for a second in the future. Would one be OK for the aforementioned easy plants? Should I be concerned about the lack of white LEDs? I also can’t seem to find G+ for online sale in the UK so this doesn’t seem a viable upgrade over the G.
Edit to add - I know outdoor floodlights are an inexpensive way to get good aquarium lighting but given the restrictions I have around DIY, needing a lid and visible light sources, I’m not sure I could make this work. But I am open to the suggestion if anyone can help me envisage how I could mount them. I can make a mount bar out of wood but that seems like a recipe for mold!
I realise this is a very specific request with a lot of inbuilt obstacles, so I’m mostly hoping someone has dealt with this tank or similar and has some insight. Or is a complete tech nerd with an encyclopaedic knowledge of the lighting market 😂
Thanks in advance!
(p.s. I know the poor tank is going through an ugly phase, please be kind)
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