can you have too much light?

[nguyendetecting]

Too much light can't be bad for plants. BUT a the same time the only way it would harm the plants I think is if algae broke due to the excess lights. If you don't have a good balance you would in turn hurt your plants.

putting a planted tank outdoors in the sun is a good example of lots of light and not enough nutrients. Or ponds that get overrun by algae.

Here is a pic of my 75, with 4 26watt spiral cfl, and a 36t5 bulb. If my co2 runs out algae breaks out within a month if i don't cut the lights down.

good luck with your hood btw, be mindful of the advice ppl add they're just trying to help. and yea they can seem mean, but r just looking out

 

[tanker]

Well, I'll repeat the old mantra: It's all about balance.
The higher the light, the higher the amount of nutrients needed, and the higher the amount of co2 needed.
Just make sure it's all in balance.
However, extremely high light is a walking a tight rope, one little mistake and it'll be algae city.

:iagree:

Really that is the bottom line---Balance. I think I have LOTS of light and I do at about 4-5 watts per gal. I do not have any algae issues--(ever??, Well that is a differeent story). I must maintain my CO2 and ferts. If my CO2 goes out --I MUST lower my lights. There have been times when my CO2 goes out and I do not catch it in time I can get algae in 2 days---and lots of it. The same may happen if I do not do any ferts (but I have lowered my ferts W/O any issues).

Plus side---My plants grow quick!!!!

My under-water jungle--and this is after a prune and clean!!

 

[plantbrain]

:iagree:

Really that is the bottom line---Balance. I think I have LOTS of light and I do at about 4-5 watts per gal. I do not have any algae issues--(ever??, Well that is a differeent story). I must maintain my CO2 and ferts. If my CO2 goes out --I MUST lower my lights. There have been times when my CO2 goes out and I do not catch it in time I can get algae in 2 days---and lots of it. The same may happen if I do not do any ferts (but I have lowered my ferts W/O any issues).

Plus side---My plants grow quick!!!!

My under-water jungle--and this is after a prune and clean!!

So, what is easier, using LESS light or more light?
Do not answer that, you already did.:thm:

The highest ranking ADA contest tank from the USa and most of the top ranking tanks had a mere 40-50 micromol of light which is certainly at the lower end.

My own tanks have about the same amount as well:

The question is what is better overall management and care, what makes it easier to keep up on, to be able to neglect somewhat and get away with fewer dosing, pruning, etc and still have good looking tank/plant health regardless of the scape or plant species?

Which CO2 level will be easier to match? High light, or lower light?
Which CO2 concentration will place less respiratory stress on fish?

It's not higher light.
What is the largest source of wasted $ and energy consumption on planted tanks? Excess light.

What makes all CO2 and nutrient management easier?
Less light.

Will plants grow faster with more light, if CO2.nutrients are non limiting?
In general yes, up to about 400-600micromols.

But who wants super weedy growth that's touchy?

Patience gets you a lot more than speed alone, there's a balance there as well. My tank above uses lower light, under 2w/gal and that's a 24" deep tank and the hood is another 12-14" above the water, using PC lights.

this one uses 1.5 W/gal t5

Also, about 40micromols at the bottom.

Here's another, the w/gal are higher, but the intensity still the same(40-50micromolsat the tips of the plants), distance from the lights is more, so light is less intense, that distance issue makes a large difference when it comes to the actual light the plants receive, so watts/light type/tank size etc is not all of the story and makes a poor comparison.

More is not better, it's just more work and stress for fish and the aquarist.
I rarely see folks stating that as their goals for planted tanks though.

Regards,
Tom Barr

 

[iamvictor2k]

thanks yall. this is my first planted tank that i am going to experiment with. i had a 55 that didnt have good light no co2 and minimal filtration. i want to do this one right and have fun experimenting with it. this is why i made my light the way i did. i have 2 timers to simulate morning noon and night. and i over did the lights so i could fined my ballance. i was unaware of what i would need as i havent seen many diy lights like i have so i can alwase remove or add some lights if i need them.

 

[jbradt]

IMO... too much is a relative term. In this case relative to the amount of upkeep you want to do to your tank. The more light, the more ferts, co2, etc you're going to need to add and keep track of. The slightest mistake in dosing regiment could turn into a huge headache. I would figure out how much you need based on what type of plants you want to keep and go with that. It'll help to keep it simpler and IME, more enjoyable.

 

[plantbrain]

For a 55gal, 2x54 W T5 is plenty if not too much even.
Better option might be DIY t8's. Say 3 of them spaced evenly across, and run them say 9 hours a day.

Good current, good CO2, good sediment, good dosing and care.
There's no plant you cannot grow with that amount of light.


Regards,
Tom Barr

 

[gmh]

If you have a low tech tank (no CO2 added), 2 watts per gallon is a decent rule of thumb, depending on the tank dimensions and type of bulb. More than that, and you will likely have an algae problem unless you add in CO2 or cut back on the photo period.
What size of tank and type of bulbs are you talking about?