Looking for a skimmer for a 20 gallon..
- Thread starter d00d
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PAR (photosynthetically available radiation) and PUR (photosynthetically available radiation) meters determine how much usable light is reaching the depth of the tank in question. For example a 9w light consisting of CREE LED's are capable of putting out ~4400 lux or 100-150 PAR at 14" deep, which is far beyond the minimum light threshold for most corals. This is comparable to a 70W metal halide at this depth. so no, halides are NOT needed to grow SPS.
Oh yeah, at the same depth an 18W PC light will only put out 2080 Lux or 42 PAR.
You brought up the lighting being good enough.. which I am not arguing against.. just the fact you are using PAR as your reasoning is the only reason I question you. 
PAR is todays WPG... and it is just as useful as WPG as a reading by itself. PAR tells you nothing about how good the light is because I can make a red light that puts out 3000 PAR at any spot in the tank, yet all my corals will die from that type of light even though it falls within the PAR spectrum.
PUR, there is NO definitive measurements for and every coral (even within the same species) can have different PUR requirements.. but again, there is no scientific tests done on PUR levels (there really isn't a method to even test PUR).
Just trying to clear that up so you don't go around giving misinformation to others, that is all.
The best tool to use for lighting today is a Spectrometer, but a good one cost around $3000+ so it is very cost prohibitive for most home users to buy one. Next best thing we can go by is that pretty little chart with the spectral output of the bulbs printed on most bulb boxes, but again, that isn't even the most accurate because every ballast will run bulbs slightly different and give different spectral graphs. Plus the chart on the box doesn't tell you how long the spectrum will last in the range printed so you really have no idea on the lifespan of the bulbs..
PAR=Photosynthetic Active Radiation. PUR=Photosynthetic Usable Radiation.
The more you know...
PAR is todays WPG... and it is just as useful as WPG as a reading by itself. PAR tells you nothing about how good the light is because I can make a red light that puts out 3000 PAR at any spot in the tank, yet all my corals will die from that type of light even though it falls within the PAR spectrum.
PUR, there is NO definitive measurements for and every coral (even within the same species) can have different PUR requirements.. but again, there is no scientific tests done on PUR levels (there really isn't a method to even test PUR).
Just trying to clear that up so you don't go around giving misinformation to others, that is all.
The best tool to use for lighting today is a Spectrometer, but a good one cost around $3000+ so it is very cost prohibitive for most home users to buy one. Next best thing we can go by is that pretty little chart with the spectral output of the bulbs printed on most bulb boxes, but again, that isn't even the most accurate because every ballast will run bulbs slightly different and give different spectral graphs. Plus the chart on the box doesn't tell you how long the spectrum will last in the range printed so you really have no idea on the lifespan of the bulbs..
PAR=Photosynthetic Active Radiation. PUR=Photosynthetic Usable Radiation.
The more you know...
LOL.. I am getting a kick out of this thread now.. as I sit here looking at my 29G SPS/Anemone tank that gets neglected like no tomorrow, reached 86f the last 3 days in a row, simple as can be tank and the SPS corals (I admit, easier SPS corals like Green Slimer, monti cap, and Poccilopora) that are growing like crazy, even with being stung by the anemone on a regular basis. 6x 24w T5HOs on my tank, 4 actinics, 1 75/25, 1 10k. so 144w of light.
With age and experience comes confidence.. and I am finally to the point I am confident a 29G tank with just a HOB filter, heater, and 2 powerheads with adequate lighting and regular water changes can grow full of SPS corals. Is it an ideal tank for SPS corals? Obsolutely not, but can it be done successfully, you bet it can.
Not trying to disagree with you Toejam to start trouble, I think your advice you give on here is top notch.. just this time I have a different view on it.
d00d... PAR meter what? Please, by all means enlightened one... tell me how a PAR meter tells you anything about if a light is adequate for an aquarium.
Actually I am in agreement that it can be done.
I have a choice to make here when I advise people: Lead them in the direction that has the best chance of success or take the risky advise route. In this case I find it more risky to advise going 29g full sps with ok lighting is not a recommendation I would give.
Can it be done....im sure it can because I had a 29g tank myself with more crapy lighting (PC) and I was able to maintain some easy going SPS.
It's not we disagree on anything. You feel he will be fine with his lights going all out SPS reef ..even with the more sensitive species. I just think it will have higher chances of loss because of his lighting. Not that it can't be done.
So keeping in mind of wanting him to have the greatest ease of less maintenance (cause im lazy so I give the lazy mans advise) and growth +lower chance of loss... I didn't want to recommend going with just 96w of that lighting for a full SPS tank.
Pendant 150w would be my advise if he plans to get the SPS forest going and having any species he wants in there (as long as it can fit). With that advise my only concern from there was heat.
This spun out of control now as i glimpse where this thread has turned...
There is NO NEED for being confrontational here... Advise is just that...not a do it or you fail thing. You don't like the advise thats fine. If it helps you and you use it, Awsome.
Thats the purpose of these forums..for us to share our experiences...advise...if I you disagree thats good... Provide me with why and teach me something new... That is why I come here.
But I do not come here to see confrontational type postings and attitudes...this place was just fine without them..>It should stay that way.
PS Correction 20gallon long where ever i posted 29g
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LOL, that post was like Quentin Tarantino's latest movie... about 30 minutes too long.. hahahahaha. I got the point and you are correct.
The lighting turned into a question, and no one really disagreed the lighting would be good enough. Like you said, best chance of success would be a different route. I feel the biggest challenge he faces isn't the lighting, but keeping proper water parameters, which is usually the hardest to learn and maintain at pristine levels. I know it was for me.
The lighting turned into a question, and no one really disagreed the lighting would be good enough. Like you said, best chance of success would be a different route. I feel the biggest challenge he faces isn't the lighting, but keeping proper water parameters, which is usually the hardest to learn and maintain at pristine levels. I know it was for me.
This is what I am referring to. This is what starts arguments and pisses people off.
You simply could have left that condescending line out and I wouldn't have had any problems with a disagreement. You crossed my line with that bullcrap right there.
I gave you the respect you deserve as I posted politely to you from the start. I expect the same out of you.
Well I hate it when I dont communicate well enough and a post gets taken wrong so sorry for the long post I replied with.
Yah that also crossed my mind....
BACK ON TOPIC:
I still think hob skimmer is beneficial regardless. He could go without ...it just means bigger water changes and maybe more frequently....depending on how much coral he gets going....feeding...fish..etc...hard to say.
I vote on the Reef Octupus or Bakpak brands myself.
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Puff puff pass man.. you are getting worked up over 1 little line on the internet. Take a deep breath and forget about it.
:hypnotized: :grinyes:
:hypnotized: :grinyes: