If those readings are accurate, I believe they are too low.
How old are the MH bulbs?
The bulbs were new,now they are 9mos,got them for xmas
[quote=“beadlocked450r, post:12, topic:5770”]
Does polyp extension mean somthing?good or bad?[/quote]
The only more complicated question could be trying to figure out why women are mad at you.
Polyps can stretch trying to reach food they’ve smelled in the water. Polyps become longer in longer flow that will hold them up. Polyps can retract if a fish, snail, sea star, or other critter touches them. Polyps can stretch out to reach for light or shrink in when they are getting too much light or stay in when they’ve given up on getting enough light. So polyp extension is a great deal complicated.
Stating you aren’t sure what type of bulbs you have is like posting in a car forum that you aren’t sure what is under your hood. If an engine is an engine then a T5 bulb is a T5 bulb. ATI bulbs (brand name) will make an immense difference. T5 bulbs also should be replaced before they reach 10 months old.(some even say ever 6 months) I shoot for every 6-8months depending on when I get two seconds free time to do so.
How deep is your frag tank? Is this a 5 gallon tank? 75gallons?
Frag tank is a 36" 30 long, with 6 39w-3 blue plus 1 fiji purple 1 aqua blue special and a bulb with no tag,all bulbs are ati, I’m not sure their age as I got the fixture used from paul,but as I said in an earlier post these bulbs are keeping my derosa clam alive when my mh couldn’t.
that is a very well lit frag tank… assuming the no name is not actinic, then your blasting the 450-460 range… those blueplus and aquablue put out the par!
i’d guess 400 and then some at the top of the tank…200ish at the bottom… every bit off that tank is covered with light… that light would make a nice 65g reef!
well, there’s one huge difference… PAR
First off do NOT replace them all at once if you choose to do so. It is important to replace them slowly or you WILL shock your animals. That does sound like a lot of light(if they were new bulbs) however Paul purchased his bulbs last ~11 months ago. I am not sure how long they were not in use, but if you know they were only off his tank for a couple days before you started using them it is time to replace them.
When I say a lot of light… in my opinion it is a good amount, almost too much, but ok as long as there is enough flow. 4 bulbs would work fine and be plenty. 7 would be overkill. 2 little, but still grow things. (this is all assuming decent reflectors and ballasts)
Either too little or too much light could lead to duller colors and polyps extension that is not ideal. It may be wise to stick a par meter next to the mother colony and compare with where the frag is. Take notes of your bulbs age. (Front bulb replaced 9/15/2012, second from bulb - unknown age, all bulbs cleaned 10/1/2012 and so on)
Just my two cents.
The end of life of a bulb depends on the brand and operating conditions. MH near the end of their prime will slowly start to go down hill in par values. There is typically not a huge difference between a MH bulb at 11 months and 13 months. There is typically a massive difference between a T5 bulb at 10 months and 12 months.
Best as my memory can serve anyways with out digging out the research and papers to verify. If you want hard facts versus my crappy memory search for “Dr. Sanjay Joshi T5”