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Is my lighting to much?

Mikeyd

Member
Joined
7 Jan 2013
Messages
41
Hi,

I have a Juwel lido 120 which is almost 2ft deep with 2x24w t5 bulbs and reflectors.
What are people's opinions in my lighting levels, too much for low tech? They are on for 6 hours per day at the minute.

Thanks

Mike
 
I think 6 hour's is good place to start.After three week's , assuming plant's are doing well, and alage is not an issue,then I might increase to seven hour's and after another three week's,maybe eight hour's and so on.
 
I think the T5's you have maybe to powerful for a low tech set up (especially with reflectors), without Co2 injection. With high lighting your plants will demand greater levels of Co2 and ferts. If you don't supply these elements your plants may suffer as a result.

Below is a quote from a great little article, which should explain a few things about balancing you tank (The Balanced Planted Tank)

"Understanding the balance is the key to any planted tank. Any successful planted tank will be a balanced tank. These are a couple of things that the hobbyist often hears about, but many do not understand them or their implications. The purpose of this article is to introduce the reader to the balance, explain why it is important, and how to achieve this balance.

First, what does the balance consist of. The balance in question is the proper proportions of light, carbon dioxide, and nutrients. Plants require all three of these things in order to survive and grow. In order for the plants to take in the nutrients, there must be CO2 and light present. When any one of these three things is out of proportion there will be an outward sign to let the hobbyist know that something is not in balance. The amount of nutrients and CO2 required will be dictated by two things; lighting level and biomass of the plants, therefore, the appropriate levels for nutrients and CO2 will be different for every tank.

This brings us to point number two; why the balance is important. Plants, unlike algae, need CO2 in order to photosynthesise, without the presence of CO2, the plants cannot take in the nutrients and thus it leaves them for algae to use. Likewise, if there are too many nutrients present for the amount of CO2 in the water, the plants will not be able to use it all up and some will be left for the algae. Light comes into play in that the more light there is, the faster many plants will photosynthesise. Because of this, there will be a greater demand for CO2 and nutrients. So as there is an increase in light, there must also be a proportionate increase in CO2 and nutrients. Just as each one of these elements can be too high, they can also be too low. If the lighting is too low then there will be an excess of CO2 and nutrients, and there will be dying plants. If nutrients are too low, then the hobbyist will have a situation where there is nothing for the plants or for the algae. In a case such as this the hobbyist will get a nice thick green mat of cyanobacteria, also known as Blue Green Algae."

Hope this helps?
 
Sorry I should have mentioned its not a new set up. The reason I was asking is that I am having some algea issues so am trying to think about possible causes.
I'm noticing that there tends to be less gda and gsa on the glass of the higher flow areas of the tank.
 
Thanks all! Lee, that's a helpful post. I think it could be a case of having a play with some of the variables to see what results I get.
I may start with removing the reflectors and see if that helps. I'm not too sure how long I should leave it to see if things improve, a few weeks maybe?
 
I've got a big algae problem too, i've increased co2, got a more powerful filter and now i've just reduced the lighting levels, too early to say if its helping but so far the signs are good.
 
Hi all,
I have a Juwel lido 120 which is almost 2ft deep with 2x24w t5 bulbs and reflectors. What are people's opinions in my lighting levels, too much for low tech? They are on for 6 hours per day at the minute.
I think that is quite a low level of light, just up the plant mass. I've got 2 x 24W T5's on both my 60 litre tanks, on a 12 hour day. This tank is no added CO2 and no added fertiliser, regular water changes and sand substrate.
top_view.jpg

dicrossus_clup1_resize-1.jpg

Plants, unlike algae, need CO2 in order to photosynthesise, without the presence of CO2, the plants cannot take in the nutrients and thus it leaves them for algae to use. Likewise, if there are too many nutrients present for the amount of CO2 in the water, the plants will not be able to use it all up and some will be left for the algae.
On word for that, b*llocks.

cheers Darrel
 
Hi all,
I think that is quite a low level of light, just up the plant mass. I've got 2 x 24W T5's on both my 60 litre tanks, on a 12 hour day. This tank is no added CO2 and no added fertiliser, regular water changes and sand substrate.
top_view.jpg

dicrossus_clup1_resize-1.jpg

On word for that, b*llocks.

cheers Darrel


Sorry having a dumb moment, why would increasing plant mass help?

Thanks
 
Hi all,
Sorry having a dumb moment, why would increasing plant mass help?
No, it is a perfectly sensible question. The advantage of having a large plant mass is that it makes tank management a lot easier, you don't tend to get much algae, and water quality tends to be much better. I'm not entirely sure why, it may just be a shading effect, in that some leaves within the canopy are at the point where light, CO2 and nutrient levels are balanced and any leaves that are below light compensation point will be discarded by the plant.

Because I always have floaters (or emergents) these aren't CO2 limited, and as long as they have sufficient nutrients can make use of all the light energy. If you think of a plant like Limnobium or Pistia, growing on a nutrient poor river in Amazonia, it is receiving a huge amount of light energy for 12 hours every day, but it isn't damaged by all the "excess" photons. Have a look at the images on this page, they show this really well: <Amazonian Fishes and their Habitat> .

Because I don't add CO2, and all my tanks are nutrient depleted, the orthodoxy would be that I should only be able to use low light levels over a short photo-period, but I use whatever light I have on a 12 hour day, and then just adjust the plant mass until the plants are a reasonable green and look reasonably healthy. After that I use the the "Duckweed Index" fertiliser regime <Low maintainence, long term sustrate | UK Aquatic Plant Society> to keep them ticking over.

I've had tanks under 400W SON-T grow lamps in a glasshouse, and it still works as a technique, it really is a KISS solution. All my tanks are jungles, and I don't grow any "light" (CO2) demanding plants, and my suspicion would be that it wouldn't work with an iwagumi etc. The only success I've ever had with carpets was Hemianthus emersed on top of a HMF filter, and Riccia as a surface scum.

cheers Darrel
 
Below is a quote from a great little article, which should explain a few things about balancing you tank (The Balanced Planted Tank)
Lee, you need to stop making unauthorized sojourns into The Matrix. It can be dangerous.

On word for that, b*llocks.


Quote of the day.

The OP needs to identify the algae species. That will determine the likely cause, however, reducing the light intensity is an easier and more rational approach to solving the problem.

Cheers,
 
It looks to me like there could be a few varieties of algae unfortunately. GDA, GSA and some sort of hair algae.

Does this help at all?
 
Well, GDA is a real problem. I'll not sugar coat it for you. It's probably the worst algae of all and the most difficult to get rid of. It is a prime indication that the tank was set up with any combination thereof of poor flow, too much light, poor CO2 and possibly poor nutrition.

The appearance of GSA is due to any combination of poor CO2 and poor PO4.

Hair algae or any filamentous algae occurs due to poor CO2.

Therefore you have a long way to to in order to fix your CO2. Since this is a non-CO2 enriched tank (I assume you are not dosing liquid carbon) the only way forward is lots of elbo grease and an immediate reduction of lighting period and intensity. If you look at Darrell's photos in post #8, you'll see that there a re lots of floating plants, which allows less energy penetration into the tank. You can do the same if you don't mind floating plants. You can float anything you want (as long as it floats and doesn't sink). If you can disable one of the bulbs that would be great.

Cheers,
 
Oh dear! Well thanks for all the info. For starters I think a good clean, removal of the reflectors and lighting reduction are in order then. I'll definitely look at adding some more plants too before increasing the lighting period.
 
Right, I've had a really good clean of the tank and filter. I have also added an extra power head, covered one of my T5 tubes and removed the affected leaves. Below are some pictures of the leaves before I removed them. Do these look like the types of algae that I mentioned?
Many thanks.

1A07Fax.jpg
VgenFs6.jpg
dtCk9rg.jpg
KOaS5zf.jpg
 
GDA usually forms on the glass. This might be Rhizoclonium, but the root causes are similar, poor CO2 an low nutrient levels combined with too much light and probably poor flow/distribution.

If you are not enriching the tank with any form of carbon then you really ought not to be pumping so much light into the tank. Yu would be better off using T8s or low power LED.

Cheers,
 
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