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Topic Review (Newest First)
Today 02:48 PM
JPrice904
Quote:
Originally Posted by bigred87 View Post
Waaaait!! so Hoppy if i place a Home Depot 2 bulb Diamond Plate Shop Light on top of my 60 gallon ( 24in from the gravel) I am going to have Medium light???
I have a similar question. I have the standard tank lights set up on my standard 55G. I have fake plants right now but looking to get into a low light setup. I have a sand substrate so I will supplement with tabs.

I was considering getting the diamond plated shop light from HomeDepot but now I'm concerned that will give me too much light and I just wonder if I should stick to my 2 15w T8 bulb setup (one per ballast). I would rather not get into CO2 but I would like to achieve moderate growth.

My question would be before I purchase this shop light should I stick with the 15w x2 (30w) setup or spring for the shoplight? I think from looking at your chart, my current setup, would give me 20-30 PAR which would achieve a low light setup. That's looking at the black line defined as "one bulb with typical white inside".
03-28-2014 03:43 PM
Seadon
Quote:
Originally Posted by greenmerc View Post
Hello there! Very nice thread! Im gonna be working on a planted tank in April. Was wondering what type of light I would need for a 80"x24"x18" tank, im planning to go low tech w/o co2 and growing low-med light plants. I think whats available here in my area is quite limited to all purpose bulbs for the home, no special ones like LEDs, metal halides and so forth. Ive seen CFLs and T8s. Any suggestions in terms on what PAR rating i should be looking into?

The 1st through 3rd or 4th page will help you out immensely if you are thinking about HOT5 lighting...especially the part where hoppy talks about fixture spacing for tanks 18" across and more. I believe someone w/ a similarly sized tank asked a similar question, I.e. A 72"x?x? Tank...I would definitely suggest a sticky for this thread if you are looking for the right lighting, it has saved me a ton of trial and error, that's for damn sure!


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03-28-2014 08:39 AM
greenmerc Hello there! Very nice thread! Im gonna be working on a planted tank in April. Was wondering what type of light I would need for a 80"x24"x18" tank, im planning to go low tech w/o co2 and growing low-med light plants. I think whats available here in my area is quite limited to all purpose bulbs for the home, no special ones like LEDs, metal halides and so forth. Ive seen CFLs and T8s. Any suggestions in terms on what PAR rating i should be looking into?
03-27-2014 11:09 PM
Seadon The coralife will be about 2 inches from the surface so 20-21" from substrate.

The aquaticlife about 4-6" from the surface so 26"+ from substrate.

Both fixtures are on the PAR chart on the first page, I'm just reading a few pages on where hoppy says it might be better to use 2 shorter fixtures side by side on an 18" wide, or maybe it's 4 small fixtures, 2 on each half of the tank, I need someone to clarify lol.


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03-27-2014 11:01 PM
Seadon Hi I have gone through the first few pages of info on here and I have 2 questions, 1 does anybody know if a 30" 2 bulb HO coralife fixture is enough to fully light a 29 gal 30x12.5x18H without many dark spots, meaning areas where plants won't grow.
2. Similar question but a 75 gal. 48x18x20H and a 36" 4 bulb HO aquaticlife fixture


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03-27-2014 04:23 PM
Seadon The 4 bulb fixture is really for my 75 gallon tank that isn't complete at the moment, so I was using it as interim lighting until the fixture meant for this tank arrives, but if it doesn't come today taking 2 bulbs out would'nt be a bad idea. I'll have to comb through here a little more carefully I guess and see if I can't find what I'm missing


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03-27-2014 01:53 PM
newbieplanter
Quote:
Originally Posted by Seadon View Post
Ok so I have 36" 4 bulb i sitting on the rim of my 29 gal. And I'm getting moderate algae growth, I plan on switching to a 2 lamp 30"coralife fixture this week, will this solve my problem or is co2 a must?


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Instead of getting a 2 bulb fixture why not just turn 2 off or take em out of the fixture u got now? If u read this post u will see that all those things lights,co2,ferts along with plants have to be in sync an u should have low to no algae. The Man who wrote this will tell u what u need to get it under control, but i think its also writen in here whT type of light u have weather it be low,med, or high.
03-27-2014 11:56 AM
Seadon Ok so I have 36" 4 bulb i sitting on the rim of my 29 gal. And I'm getting moderate algae growth, I plan on switching to a 2 lamp 30"coralife fixture this week, will this solve my problem or is co2 a must?


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03-12-2014 03:41 PM
xfatdannx I didn't see mine on that chart, its a ZooMed dual t5ho and the reflector is mirror like...its bright!

so if it has that real nice reflector, are you in essence, shining two bulbs at once or do you lose some of the reflected light?
03-11-2014 04:35 PM
Hoppy
Quote:
Originally Posted by Shark_ View Post
This is awesome information. Now we need the plant database updated with PAR values required to grow each type of plant. Otherwise measure by PAR seems pretty useless.
In the low tech forum there is a long thread with a listing of "low light" plants, but, unfortunately the definition of "low light" was a watts per gallon definition, making the list just barely more than useless. In the Aquatic Plant Central forum there is a great "plant finder" list, but it, too, lists the lighting needed for each plant in terms of watts per gallon, greatly reducing the usefulness of the list. It will be a long time before there is a similar list that includes the PAR needed to grow the plants well. Someone who is looking for a good project should take this on
03-11-2014 04:28 PM
Hoppy
Quote:
Originally Posted by xfatdannx View Post
There is SOOO much info here i am very happy for it. I am trying to get the right balance between light and Co2 now for a high light tank. I have a 20g Tall (aprox 24in from light to substrate). Currently running two t5ho bulbs one at 6500k and one at 5000k. Would you suggest a change to get to high light or would you say i am there? I seem to get algae blooms when running both lamps, not sure if this is too much light or inadequate Co2. Thanks for any help you can provide, you have already done so much Hoppy.
If you look at the chart in the first post in this thread, the PAR you get from a T5HO light depends on who the manufacturer is - actually on how good the ballast and reflectors are. The color temperature is not a consideration when looking at PAR. Color temperature does affect what the tank will look like when lighted with those bulbs. And, the spectrum of light produced by the bulbs affects how much of the PAR emitted by the bulb is readily usable by the specific plants you are growing. But, that is another subject.
03-11-2014 03:19 PM
Shark_ This is awesome information. Now we need the plant database updated with PAR values required to grow each type of plant. Otherwise measure by PAR seems pretty useless.
03-11-2014 12:29 PM
xfatdannx There is SOOO much info here i am very happy for it. I am trying to get the right balance between light and Co2 now for a high light tank. I have a 20g Tall (aprox 24in from light to substrate). Currently running two t5ho bulbs one at 6500k and one at 5000k. Would you suggest a change to get to high light or would you say i am there? I seem to get algae blooms when running both lamps, not sure if this is too much light or inadequate Co2. Thanks for any help you can provide, you have already done so much Hoppy.
02-21-2014 01:41 AM
Hoppy Here is a good article explaining what "PAR" is, by Li-cor, who make the best PAR meter in the world, as far as I can find out. http://www.licor.com/env/application...hetically.html

All PAR measurements I have heard about or seen, use PAR to mean photon flux per square meter per second, which means it is a measure of the light intensity at a surface, not the light emitted by a source of light. I would welcome a link that says PAR is a measure of the light emitted by a source of light.

Here is another article that somewhat clears up the difference between "PAR" as a measure of what the light source produces and what the intensity of light at a surface is. http://openwetware.org/images/e/e8/Conversion_lux.pdf It seems that our "PAR" should always be called "PPFD" instead. But "PAR meters" don't measure the total emission of light from a source, but the PPFD at the surface being illuminated, a much, much more useful parameter.

Curiously, note that, for a cool white fluorescent source, the factor to multiply lux by to get what we call PAR, is .013, or 1/77, remarkably close to the 1/78 that I found experimentally.
02-20-2014 09:59 PM
Dskudera124 [QUOTE=tyronegenade;4333993]

From the data accumulated at http://www.apsa.co.za/board/index.php?topic=4454.0 (in 2010) it is calculated that, on average, you get about 1 PAR/W from tube/fluorescent lamps (T8 & T5). (T5s are only marginally better for output and this is due, mostly, to geometry.) So a 20 W CFL will put out as much PAR as a 20 W T8 tube (because the physics of light emission process is the same). Of course the CFL is all twisted and a lot of light is lost among the twists and turns of the tube (especially as about 30-40% of the light emitting surface is facing another light emitting surface and gets lost by "squishing").

The major factors (that will vary with each aquarium setup) are the turbidity of the water (the more light absorbing dissolved solids the more light is absorbed with depth), the amount of light lost to reflection due to surface disturbance or angle of lamp to water (90% of the light hitting the water at 60o is reflected and it gets worse the shallower the angle). You need the lamps as close to the water as possible to keep the angle of incidence steep. The quality of your reflector is also critical. With a bad reflector you are probably getting less than 50% of your light into the tank. With no reflector the value is closer to 30%. A model to determine reflector efficiency is available at http://www.apsa.co.za/board/index.ph...41393#msg41393 .

Essentially, if you can engineer a reflector with high efficiency and place it so that as much light as possible hits the water's surface of the tank, then you can, with some certainty, use W/m2 to estimate PPF at specific water depths.

So, to summate by example: if you have two 30 W T8 tubes they are emitting approximately 60 PAR. If you have a good reflector that can focus all the light into the tank (which is impossible but lets just pretend) which is 36 x 12 inches in surface area you will get 222 PPF (PPF = PAR/(0.9 x 0.3 m)). Assuming 70% of the light actually enters the water, this will mean you will have about 99 PPF at 15 inches of water depth (not tank depth). More than enough for Glosso and HM and unless you have ample CO2 and nutrients you will get an algae soup. Without reflecors the value would be closer to 30-40 PPF which attests to the old adage that 2 full length tubes are enough to grow just about any plant.


I'm having a hard time understanding this and it's relation to the chart. I have a 5.5 G tank with a 13w 6500k CFL about an inch from the surface in hood with no reflector. So I'm reading this noticing I'm losing a ton of light due to it being parallel to the surface and without a reflector but unless I'm reading the chart wrong since my bulb is probably 8 inches from my tanks lowest point my par is extremely high. I'm just trying to figure out what my par is and what category it falls in. Judging by the coloration of my plants I always thought it was low to medium-low at best. Am I opp operating at 1 p/w? So I'd need a 30w cfl for my 5.5g tank. My betta would probably think he's in the interrogation room
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