The Planted Tank Forum banner
1 - 9 of 9 Posts

·
Are these real?
Joined
·
15,720 Posts
Discussion Starter · #1 ·
Noticed a peculiar thing over the last days...

Since redoing my 100gal tank, I clean the front glass weekly, to get rid of some dust algae and diatoms. No big deal, takes probably 5 minutes out of my life.

A couple of days ago one of my overdriven T5's died after 10 months of faithful service. It was a 10,000K bulb.

Rummaging through my garage, I found an older AM Planta bulb which I had pulled out because it seemed a bit dim compared to the other bulbs. Figured I should use it up, with the newly setup tank I don't need that much light.

To my surprise, last weekend there was nothing to scrub where the Planta bulb is located. With a 5ft long tank, I have the 4ft T5 bulb, then an 18W PC (6500K) bulb to light the entire length. Where the PC bulb is, a weeks worth of growth can be seen.

Interesting... Not sure if it is the Planta spectrum, or simply the change that killed the algae. I'll keep monitoring.
 

·
Registered
Joined
·
3,279 Posts
WP - a little while ago I had to neglect any maintenance of my 75g for about a month. When I was finally able to pay attention to it, there was a pretty solid amount of GDA on the glass - mostly on the front glass.

I mention this only because I had a 48" 6 bulb T-5 Tek over it, and all I ever turned on was the outtermost two bulbs. The front bulb, where most of the GDA was, was a AM Planta.
 

·
Are these real?
Joined
·
15,720 Posts
Discussion Starter · #3 ·
It sure is possible that the change to a different spectrum bulb caused the demise of my alga, not the spectrum itself. I'll keep watching it...

For those that have multiple rows of T5 bulbs, AND some surface algae on the front glass, you could try this by replacing the front bulb with a Planta bulb, just for fun...

I might actually switch that bulb to the back, where I have considerably more growth on the glass, to see how that affects it.
 

·
Registered
Joined
·
21,012 Posts
GDA really grows best where the light is the brightest on the glass. I wonder if the Planta bulb was really as bright as the bulb that quit on you?
 

·
Registered
Joined
·
39 Posts
GDA really grows best where the light is the brightest on the glass. I wonder if the Planta bulb was really as bright as the bulb that quit on you?
Its not its brightness but the amount of light from the entire spectrum. Perhaps you mean that some light is being blocked by plants and ornaments. The same light that makes plants grow makes algae grow. Brightness for human eyes is determined by lumens which is entirley weighted to the green spectrum - not reds and blue light which activates photosynthesis.
None of you really have the correct answer.

The Planta bulb by AquaMedic is a very good plant bulb. It has very little green light in its spectral output but does have lots of blue and red emissions.
 

·
Registered
Joined
·
13,609 Posts
I think it has to do much more with intensity, not the particular spectrum of any one bulb.

To date, I've yet to come across any correlation between bulb spectra and algae reduction.

Folks carry on and on about it, but no one offers any thing other than some babble about Red and blue vs yellow and green,m which really does not say much.

Algae and plants have the same issues here.
Green algae and plants are very much alike here, even more so than other phyla of algae.

So this is not an explanation, where as a difference in intensity most certainly can reduce algae via less light and also reducing light does what else to planted systems?

Less light= less plant growth= less CO2 demand.

Maybe it's a bit of subtle CO2 tweaking that's needed for GDA.
That would explain why most of my tanks do not get even when inoculated.
The other tanks that have had it, where tweaked for CO2, it never returned after.

High light + CO2 subtle issues.
Folks that have lower light rarely have issues with GDA.

Regards,
Tom Barr
 
1 - 9 of 9 Posts
Top