Overkill?

[biomekanic]

I'm currently planning out a planted (seagrass) refugium using my CPR refugium (the big model).

Currently I'm lighting it with 2 23w 5000K bulbs in a standard 10g hood (I've replaced the reflectors with some from AH Supply trimmed down to fit the hood, it went from bright to "gah! I'm blind", I heartily endorse their reflectors).

From all the reading I've done though, seagrass needs lots of light, I was considering getting one of these http://www.hellolights.com/aqadhatamo.html and using it.

Any thoughts/ideas appreciated.

 

[Samala]

From my research I reasoned (hopefully correctly) that the minimum amount of light for seagrass over a ten gallon (so 12" in height) is about 40 watts of 6500K flavor T8 type bulb. I tested recently with power compact bulbs and found you only need slightly less for that bulb type.. about 35 watts over a ten gallon, with decent reflectors. Keep in mind thats a minimum amount.

Right now I've got shoal and stargrass growing very well under 96W 6700K PC's. That's twice the minimum amount, but it doesnt seem to be overkill.. yet. I will tell you that I lost lots of leaves out of all three species of seagrass the first week - its hard to say if it was due to light stress or transplanting stress. The grass has only been in about two weeks so I cant say anything definitively yet. I keep meaning to take some underwater light readings on the tank but always forget to bring the equipment home with me.. maybe I'll remember today.

Beyond heat concerns, I think the problem with a high light situation will be that you need to keep up with all the macro and micro nutrients required by the grass to keep them going. For instance in my 96W 10 gallon seagrass tank the small colony of seagrass will go through 10ppm nitrate in about three to four days.

I cant find specs for the CPR fuge.. how tall is it?

 

[biomekanic]

LxWxH: 25.5" x 4.5" x 12"
From the Marine Depot products page. About 4" of room for substrate on the bottom, figure 1" of clearance on the top, so 7" of water column.

BTW, did you get the PM I sent you a few days ago?

 

[Grandis]

Samala:

... yet. I will tell you that I lost lots of leaves out of all three species of seagrass the first week - its hard to say if it was due to light stress or transplanting stress. ...

The seagrasses loose leaves every week. No matter how much light they get. My experiences with seagrasses were with natural light and fluorescents tubes (VHOs). Just remove the brown leaves when they get loose from the plant.

Grandis.

 

[Samala]

Thanks for the tip Grandis - that certainly helps explain why I'll lose a few leaves every week. I was thinking it might have had something to do with my setup, but if thats the normal growth pattern then I imagine its to be expected.

I think, Biomekanic, that if I were you I would stick with the AH supply setup you've got now.. get the grasses installed in the fuge and then see over the next week or so if 1) they are growing at all and 2) if your phosphate, nitrate, etc levels are coming down the way you want. But then, I dont have a whole lot of money to push into my tanks so I'd hedge on a big investment in that cool Aqualight.. Honestly, I think the shoal grass I'm sending will adapt.

>Sarah