how much light do I need with T5s

"guinea pigs" in a 1.8m fish tank - that is worth a pic LOL. Do not stress about the lights ... once the system is up and you know what you are going to plant then it is "easy" to add more if need be. One thing that has been reiterated for me was the need for good hood reflectors .... be it bought, made etc ... I always get the feeling when I look at those big light rigs that I should only see some serious coral growing under them not the typical tropical plants we get in ZA. The other thing is most people with BIG light have BIG algae or contribute further to our CO2 footprint by adding it to the tank all depends what you want to do.

 

Thanks Ferdie, the manufactured aluminum canopy is currently being taken apart by the agents into sections and the existing T8 fixtures/electronic removed, so I can revamp this with T5s using another tech dude. So for this reason I need to establish my lighting system up front, as it would be a real hassle and time consuming to change later. I am keen to go for a variety of plants with my initial set-up, perhaps red Ludwigia, T’lotus, HCalli, weeping & xmas moss, gosso, crypts and swords, so I would probably opt for a med to hi tech scenario, although I know nothing about these definitions. My current set up in the old tank is a low light affair with java fern/moss, anubias all doing well with no ferts, Co2. I appreciate some of my existing plants might not handle the new tank set-up with increased light.

I have attached a link to another newbie tank, 75Gl with 160watts of T5s. Not that I am in awe of the tank design, but his plant selection would be close to mine, perhaps not such a variety, and I would like to carpet the foreground and the mopani, with some of the plants mentioned above. I found it interesting to see the development/growth of the plants over a month or so, as you can see how some plants are doing Ok and others not, while the green & blue army advances.

I need to make a decision this week on the T5 lights,.. presumably one should try and cover as much of the length of the tank as possible, so as I mentioned I was thinking of going for a 24w and a 39w on the same line, as it’s slightly longer and when spaced than a single 54wat. Although I understand from Altum, that a good reflector should also give a spread on the edges, but there will still be a drop off. My next decision is how many lines to go for 3 or 4? These are important things I need to decide on now, regarding the internal structure of the canopy.

Any info on how I determine the par of these T5 lights, would be great?

Here’s the link to that other newbie tank I was talking about -
http://www.aquariumforum.com/f45/my-planted-75g-amazon-tank-1969.html

 

Hey trevor, the point around reflectors is a key one... I was mentioned to me that the actual usage of the flourecent tube is roughly 45 degrees (of the total 360) which means that reflectors should give you a large improvement... consider this too... on top of everything else... I have not seen 1.8m light units anywhere and if you get them im sure they will be at a large premium.. I guess you could get 900mm or close thereto and just double up per line of lights...problems is you will have to double up on everthing and half the wattage balasts are never half the price... more like 80%...if you are worried about light covering the width of your tank then you could also consider offsetting the lighting.. ie: your first bulb being on the far left of the canopy and your second on the far right...next on far left etc... this will make sure that you get light spread accross the front... this would give you a concentration in the middle but frankly I dont think you will notice it that much.

 

So it is not just about the PAR per light but rather the overall amount of light that is hitting the plants at X depth within the 400-700nm spectrum - this means tubes (T8 vs T5) + reflector efficiency - light lost while moving thru the air and water. In the end - if you are going to all the trouble to do a retrofit of the tank T8 to T5 adding more lines and all that then I would also ensure that each line can be connected to its own timer / switch - at least that way you can "simulate" some light intensity and noon vs being a top notch algae farmer cause your lights are all on for X hours a day.

If it was me building a tank - and I would say 4 lines individual timers etc.

 

Thanks Ferdie, I take your point on the individual timers, but it would be great if I could reach a decision on what I need to time, light wise. I gather from the Prof that my original idea on mixing Grolux and Osram Skywhites might not be wise, as the skywhites '' have a strong spectral peak at 550 nm which is exactly what algae love and they will fuel algal growth no end'', I’ve now received some suggestions for alternative lights to replace the Skywhites with, perhaps the Philips 865 or Osram 965 and to be installed with single reflectors .

However there seems a variety of opinions on how much T5 light I actually require for a med to high tech 1,8m planted tank (720 lt). At the moment I am looking at going for three lines of T5 lights, evenly spread across the surface. Line 1 in the front - 1x54wat, Line 2 - x1 39wt & x1 24wt, Line 3 same as line 2.

Have I still got too much light here and are the algae gods already smiling ?

 

hey trevor, post some photos man

 

I like the Philips 865 ... have a single 4ft tube on my lucky 13 tank ... Never had Grolux and Osram Skywhites - so I can not comment on them. What you might find is that your need for light changes as the tank matures ... If you look at the list of equipment on the other form that you have set as a target .. did you see the UV filter ... bet you he had some serious algae - cause of all the light. I am in a more is less cycle in my tanks. Just removed 4 18xwatt tubes from my 4 ft and kept only a single 30W with a Juwel reflector. Not sure what will happen to the plants, time will tell. But then again I am into slow growing tanks - with MTS that is sometimes better.

Later Ferdie

 

Hey guys i need some advise, i have a small planted tank, want to be able to keep any plant except the most fussy, tank dimensions are, 60x30x30, what sort of lights do i need, i want to use diy C02 as well, im leaning to 2x24t5s sylvania luxline 6500k, but thats gna be expensive cos i need ballasts for them, or 3x18w lohuis t8 6500k? What u guys think, i want lush green plant filled tank, im coming from a reef tank background where you can never have too much light,

 

2x +- 20 watt tube of what ever you decide should be fine. 30 cm is nice and shallow - think of it this way.

substrate 3-4cm space from water level to tank brim 3 cm so you are actually only trying to penetrate 24 cm of water ... what ever you do make sure you get a good reflectors probably +- 150 each .. same thing goes two tubes do not need to both be at the same time.

Key for fast growing tank is loads of light + co2 + fertilizers - get either wrong and you have algae - or for slower growing tanks lower light and fertilizers - it all depends on your need for instant gratification.

DIY CO2 is nice to play with but not all that sustainable - doing this probably means you will soon either become an algae grower, convert to a low tech tank or go all the way .. still it is fun.

I'd go with T8's on such a shallow tank .. esp if you are gona be running two tubes.

Later Ferdie

 

If i go t8 im gonna go 3x18w, 6500k is that fine?

 

Going to be very yellow, i would add a 20 000k or 2.

 

Its actually not bad, and shows off the colour of the fish and makes the plants a nice bright green, im more worried if the intesity will be enough

 

As regards the 720lt tank (surface area 1.08m2), it looks like I am going for 3 lines
of lights. Middle and back lines made up of x1 24W T5s (either an Osram 865 or Osram Lumilux 880 Skywhite) and x1 39W T5 Sylnvania Growlux. The front line would be a T5 54W Aquastar or as suggested by some folk x 1 54W Corral Star, as that will create more attractive light for the fishies upfront ?

Any further advice or comments would be most welcome before we start drilling and refitting the aluminium canopy

 

Are you not confusing the 6,500K globes to the 3,500K "warm white", and 4,500k "Cool white" globes.
The 6,500K globes are considered the "daylight" range, and give off a very bright white light, and is ideal for plant photosynthesis.

There has been more than enough articles written on the effects of using anything higher than 6,500K globes in a tropical aqaurium... the most obvious is algae blooms, especially under 10,000k and higher.

The 10,000k and higher are for marine tanks

 

Zoom, ummm i have used the 6500k t5 osram globes (actually seen what it looks like) and ofcourse this is my opinion, but it is just to yellow for my liking. There is no rule that states that 10 000K+ tubes are strickly for marine use, and i also haven`t experienced the algae blooms, could just have been my luck, have been using 20 000k tubes on all my tanks since 2004 and just love the look of a crisp white.

 

No stress Singularity. I was just quoting what other people say about the globes. I was running 3 x 10,000k in my tank at one stage, and just couldn't keep on top of the algae. Dolphin then advised me to get rid of them and change them to 6,500k globes. The Professor and many other members who have AWESOME planted tanks also all agreed with this advise, and all confirmed that in their own tanks when they got rid of the 10,000k, and 20,000k they stopped having algae problems.

When I changes 2 of the globes to 6,500K the plants suddenly bloomed a lot better, and algae is no longer a major problem. Just my experience

 

Yea thanks Zoom & Singularity, the Prof also warned me against the Skywhite as it's an Algae booster, hence my option of perhaps rather going with the Osram 865 and mixed with Sylv Grolux with the back two lines of light. Not sure how the Oz 865 compares with the Philips Pro 965 and if the Philips is available locally? As regards the font line x1 54W, what would you recommend? I appreciate the Coralstar is primarily for marine use, but it gives the fish a great look, while the Aquastar is presumably better for plants, but is not a great colour, I understand.

I guess what I am trying to do is of course find a happy medium where the plants are happy and have the appropriate lights, but also to create an authentic natural look to the tank. I checked out that link with the various colour options/mixes and also thought Sylvania Growlux mixed with the Philips Pro 965, looked the best. As I am using 5 or 6 lights, be it small sizes, I have at least some creative options..

 

http://www.theplantedtank.co.uk/lighting.htm

 

Yea thanks Laura, that's the link I mentioned. Just need to check if that Philips Pro 965 is available locally .. ?

 

Trevor, have you considered staggering your tubes rather than a linear setup? Would make life a bit easier having the same tubes all round.

Something like the top diagram: