Fish Tank Light for 4 ft Tank 'focus on PLANTS'

Hello. It's been a LONG time since I used to keep fish. When I did I used to use florescent with a focus on Plants. I know LED is the thing now, BUT when they first came out I did not like marketing that was selling them. I have to be honest and say that I struggle a LOT with today's marketing and influence articles and no longer know who to trust. So it is that I am hoping to hear from average users that are not into selling things but just want to help.

That out of the way, I have just picked up a second hand 4Ft fish tank. L120cm W38 H46 (205Liters/54 Gals)

What kind of light would be a good pick to grow LOTS of plants. I don't want a fancy moon light or anything that does fancy colors. All I am interested in is giving my plants the best light they can have without blinding the fish. I don't care about power consumption and longevity. If fluorescent lights are less blinging and offer optimal spectral lighting with plants in mind I would like to know? Do they have a better throw or is it best to have two lights Vs one in this regard? Are fluorescents still a thing in this regard? Or has LED completely wiped them out? Do LED lights negatively impact fish at all as they seem overly bright. Like sitting under a hundred spot lights?

If you could link me up to some examples re the most suitable Fish Tanks Lights regarding best spectrum for growing plants without blinding fish that would be greatly appreciated. Fluorescents OK.

Type of plants:
Just your run of the mill variety at local Pets/Fish Shops.
I like tall ones spread throughout/runners, moss and surface plants as well.
I like to fill my tank with plants and only have smaller fish / placid fish with some bottom dwellers
But most plants and wood.

Cheers @ Ty.

I'm not a master at planted tanks, but I know a bit about them.

LEDs and fluorescents (T5s in particular) can both be good for growing plants provided you pay some attention to the spectrum of the lights and to the amount of photosynthetically active radiation (PAR) the lights give off (wattage or lumens are not good measurements). You want a light with good PAR measurements.

Blue and red portions of the spectrum are best for growing plants as these wavelengths are best for stimulating photosynthesis. This is why the LED fixture you want to throw away has blue LEDs, and this is why dedicated grow lights are purplish (they have a mix of blue and red light). You also probably want a light that shows colors well so a dedicated grow light is not ideal.

LEDs are definitely going to give you the best bang for your buck. Nicrew and Hygger brand lights are great, cheap lights. They have no effect on the fish compared to fluorescents. I have the NICREW SkyLED Plus, and I'm quite happy with it. If you look at the light its mostly white LEDs with a few red and blue LEDs. The blue and red LEDs are specifically there for plant growth.

For fluorescents, you will probably want to buy a light fixture that can accommodate multiple tubes, and you will want to buy tubes that fill out the spectrum nicely (a few different colored tubes). High tech fluorescents lighting setups are still cutting edge and can give you really impressive plant growth when done right.

Fish can be sensitive to the overall brightness of light. In reality, many aquarium fish come from environments with little or no aquatic plants. Some species of fish will prefer dim lighting that is not conducive to growing plants. The type of fixture, LED vs. Fluor, is irrelevant. The intensity of light is what matters for the fish.

Assuming you are planning on keeping a low tech tank (no CO2 injection, no/minimal fertilizer), you will want the light fixture to put out 15-30 PAR at the substrate level (PAR depends on distance from the light to the substrate).

You should look into soil tanks and plant fertilizers. When done properly, adding fertilizer and/or having a partially top soil substrate can result in really good plant growth.

Check Check and double Check - Thanks for the awesome grounding. I really needed that.

I am looking at a basic selection of tropical fish with focus non aggressive kind. I understand this will also depend on environment provided
I once had an awesome setup in a 4foot fish tank with neon's, clown fish, and a pair of Bristlenose Catfish that used to bread so many little ones. In fact I used to off load them to a local shop. I had a lot of plants in that tank with more than enough drift wood.

I'll try not to overthink but it does help to plan. I'll look into things with everything you just raised. Thanks for such a well constructed reply. Really appreciate the tip on plant growth! Will look into that for sure.

Honestly for high light tanks the cheap LEDs don't really cut it. There is no real data available for most or them on light intensity and spread so you are buying blind.

One thing to remember with LED is that the light is very directional and there is a sharp drop from the bright areas to the dark areas. This means you have to make sure the light covers the entire length of the tank. A lot of them say something like 50-80cm length. The light is only just 50cm though and the drop off is so bad on a lot of LED units that the extra 30cm on the sides will be a fraction of the brightness directly underneath. You can overcome the poor light spread a bit by raising the light higher above the tank but then you lose intensity a bit from that.

Nicrew lights are very budget. For a low light tank they can work fine. They have really terrible light spread though and output is fairly low.

Finnex is the next step up. Would class them as a medium output light. Testing the finnex planted against the nicrew light the finnex had about twice the light output. Also at the edges where the light drop off was worse the finnex still had a higher light output than the nicrew did at the center.

The fluval lights seems to be some of the best on the market in terms of pure PAR output and decent angles.

Thanks Barney. I'll be sure to get a 120cm for my 120cm tank. I thought as much when see 90cm being recommended for 120 in retail adds. That was an LED as well. Crazy how thing have got after all these years. Just as well I popped in here to ask for help. Thanks for the feed back re the brands.

I probably should of mentioned budget. For now I will be going bang for buck and invest into those higher brands a little further down the road. Things have gotten so expensive that now after financing a custom PC build I'm left a little short since discovering just how expensive fish keeping has got. I guess everything has gone up re CV.

Good to know that as I really do want good light penetration and coverage. TY.

Short term you might be able to pick up a T5 unit for cheaper than an LED unit and if you can get at least 2 tubes it will better performance than most of the cheapo led units. A couple of high output t5 6500k tubes with a halfway decent reflector is better than the majority of LED units on the market IMO (at least in terms of light spread and raw PAR output). T5 units can often be picked up second hand fairly cheaply as well as people ditch them for LED.

Over time T5 works out more expensive as you have to replace the tubes every 6 months and the running cost is a lot higher. They work well though.

I've been well impressed by the Fluval Aquasky series and currently have two of these.
Whilst they do come with what some may consider unnecessary gimmicks and are not the cheapest on the market, I've appreciated the ability to 'play' with different white, red, blue and green settings, for my plants...all of which continue to do well.
(I also appreciate the gradual 'sunrise' and 'sunset' settings).

Whilst these lights do not match the length of my tanks exactly and the point about light 'drop-off' is well made, I've found that this can be managed by careful placement and use of a tinfoil reflector and none of the drop-off is greater than that given by my floating plants.

Having become well used to the Fluorescent Gro-Lux tubes and their ilk, together with the expense of replacing tubes on a regular basis and even the starters, I'm now more than happy to stick with LED systems.

This was my review of the Aquasky.

I've gotten the impression from your posts that you want to have a low tech tank (no CO2 injection). In that case, I don't recommend getting a really strong light. High light is only good on tanks that supply lots of nutrients (fert dosing and/or aquasoil, CO2 injection). High light, high tech tanks are also very finicky, if one thing gets out of balance you can quickly have a massive algae bloom (of course if you do it right they can be extremely beautiful). If you put a strong light on a tank without proper nutrient dosing and CO2 injection, you're basically guaranteed to have algae problems.

If you're going to be growing swords, crypts, basic stem plants, java fern, vals, sagittaria, anubias, monte carlo etc. then a low light tank is fine, even ideal.

In the world of planted tanks I find there is a drive to buy the strongest light possible while neglecting other aspects of plant growing. You'll find a remarkable number of people with high tech lights run them for short photoperiods (like 4 hrs on) or never at 100% intensity. To me, this is a sign that their light is overpowered for their aquarium.

I used to have a Nicrew SkyLED Plus on my 55 gallon and one on my 10 gallon. It did incredibly with swords, red ludwigia, tiger lotus, vals, dwarf sag, pennywort, and tons of others! The red plants were looking great. I downsized to a 20 and am buying the same model again soon. I really love it, it does great. It might be a good option for you! Ibelieve the 4 foot one was $55.

Thanks Guys - Appreciated the detailed replies and especially the photo. Thanks Olive. I have a good idea of what I want in my head and whilst they may differ to the assumptions given, I am more than happy for the challenges. I love cleaning fish tanks. LOL. I used to pride myself on my previous one (so long ago)

Due to financial constraints we ended up just opting to get the following LIGHT second hand on the Face Book Market Place:

Fluval Fresh & Plant 2.0 LED Strip Light - 59 W - 122 cm-153 cm​

I know it's outdated but at least its 122cm at its shortest width so will fit the entire length of my 120cm tank. Being second hand worries me, but the image looked good. Figured it was worth taking a chance as is on $40AUD / $28.5USD I won't put many expectations on it.

Yet to pick it up. I am hopeful it will suffice to get the tank started. I'll upgrade into the higher lighting arena when I have enough gear to tackle that challenge in the months ahead. It's all second hand parts for now. Has taken a lot of time to clean it all up. I have enjoyed do such very much. Thanks again for the much needed advice. Whilst I use to be into it so many years ago, the old grey matter needed a bit of updating. Thx again. I will have more questions soon enough.