Q about light penetration to 'the depths' in aquaria..

Not much light it seems to me.
You lack intensity, even if they are 75 w ea, 2x 150w of T8's on a 125 gal tank ain't much to grow anything really, so you get decent algae near the light, but not elsewhere.

Regards,
Tom Barr

 

For what specifically?
Most macros are fine using 4-5w/gal on PC/T5 lighting.
Seagrasses might need more.


Regards,
Tom Barr

 

Ulva is a transient weed.
You need to keep the nutrients up there a bit if the tips get decayed etc.
Same with Caulpera.

You should get very healthy full growth.
Both will do better at lower temperatures as well.

Regards,
Tom Barr

 

Yes to all except PO4.
I'd not pulse that unless you have high plant density and then maybe 102x a week.

Regards,
Tom Barr

 

Cu, Bleach, medications, heck even salt, it's all about the dose.
Caffine is toxic at high levels, but folks gulp it down every morning.
TMG is not that rich, Flourish is too low in Cu IMO/IME.

You should try dosing 0.2ppm and test how long it takes to be consumed by the tank. Your test kit is only so good at the lower ranges, few can do well at 0.05 ppms or less, they just are not designed ot measure such low levels accurately.
20ppb is about where macroalgae are becoming limiting(that's parts per Billion), most plants, about 50ppb or so. Less than 20ppb : micro algae.
Plants shut down first, followed by macros and followed by micro algae.

Without testig things, it's hard to say and fear is always a favorite, but 3000$ worth of coral you have coddled for 4 years is not something I'd suggest as model to test.

Macro algae and fast growing seaweeds make a better model to explore the interactions. From there, you can go back and see what things might work well and make more predictions on a coral tank.

But....many folks even with low PO4/NO3, huge skimmers, stilll........have their corals die and other issues not related to higher PO4/NO3 and macro algae, so keep that in mind when they bellyache and fear mionger loudly.

There maybe issues with some species, there are always exceptions, but we are after generalizations and patterns.





Regards,
Tom Barr

 

BTW, see the scaper of the month (a neglected part of the site, Greg and I are both grad students studying full time, so we can let things lapse here an there)

It has a lot pics of cold water macros from the nutrient rich deep upwelling along the coast of the Western USA. I've already been very successful with tropical Carribean species and when in Rome, eat pizza.
I live in CA so I use what is around me, the redwood, the rock, the macro algae, the manzanita etc.....
I am keeping them in a 40 gal cube and will get some pics in about 2-3 months.

No one has been successful at artifical media and seagrasses here.
Well, Monterey Bay Aquarium has some seagrass in their kelp tank, but the kelps die fairly quick. They cannot grow the grass anywhere else.
It's due to high wave energy and lots of light for the success in the one spot, the system is all open water so the nutrients and other parameters are all uniform.

Still, if I can identify good horticulture methods, restoration efforts can be used for many of these and better understanding and use in sceince.
Hard to use something you cannot grow in the lab for a test model




Regards,
Tom Barr

 

Reef folks are not big authorities with macro algae as it is.........
I get questions all the time about what is it? Why is it growing etc......
They are as clueless as any newbie.

I'm not sure a reference or two is going to convince them or anyone really.
The (Florida) SFWMD did studies on PO4 removal in treatment marine wetlands.
The same applied to the FW systems.
I'm not sure they have published it, but it's available.

They use plants for nutrients removal and sequestrration, which is precisely what folks here do with FW and Marine plants very often.

That does not really matter either, you can find studies that show a clear ecological niche as the size of the autotrophic organism decreases, so does the amount of nutrients required in it's environment.

Do you find small femi plankton in coastal upwelling regions or in the extremely nutrient poor central gyres?

Regards,
Tom Barr

 

Well, why worry about what the other folks not using macro algae are doing?
I'm not trying to convince them.

Let them think that and then you keep showing them nice examples of macro algae and tell them how you dose to keep them.

Evidence is not going to convince many folks, pictures do a better job.

See my tank here for example:
There is not a single coral in this tank, it's entirely made from macro algae. The damsel I could never catch, I wanted blood shrimps etc, but oh well.

Post or link these pics to them and see what they think

Regards,
Tom Barr