Lighting Upgrade...Looking for advice

[Spoon]

I am upgrading the light on my 45 Gal planted tank and I was hoping to pull from your experiences. I currently have two 15 Watt bulbs and I will be getting a 96 W power compact. I believe I can keep both lights on the tank for a total of 126 W, Giving me 2.8 W/gal.

The current setup includes 14 Silvertiip tetras, 5 Rasbora, 2 Discus, 1 Angel and 1 lonely neon.

I also have a couple of anubias, two crinums and some Java Fern.

I am upgrading the light because all of these plants were doing much better in the smaller 20 gallon tank but when I moved to the 45 growth has all but halted.

Is there anything I should do to acclimate the fish and plants to the new light?

How long should I keep the light on?

Should I raise it off of the top of the aquarium for a couple of days to make it less intense?

Should I expect an algae bloom? Is there anything I can do to reduce that possibilty?

Thanks

 

[Guest]

Normally the photo period on a planted tank should be between 10-12 hours a day.

You can expect a algae bloom unless you have your nutrients balanced and a high number of fast growing stem plants. Right now the thing restricting plant growth in your tank is light. Once you increase the amount of light the restricting agent will be something else. Nutrient imbalance is the most common cause of algae. If your nutrients: Light, CO2, NO3, K, PO4, Fe, and traces are in balance then your higher order plants will out grow the algae and keep it to a minimum.

With the plant load in your tank and your increase in algae I would expect that you will see some algae problems. Do you know what your nitrate and phosphate levels are?

I would guess that the plants did better in your 20 gallon because you had at least 1 watt per gallon on it. With the 45 gallon you have .667 wpg which is not really enough light for even low light plants.

 

[Spoon]

At the last check the nitrate levels were 0 and I think my phosphate is pretty low. I use RO/DI water for all of my water changes and for topping the tank off.

I probably should get a water test soon though. The Silvertips are relatively new.

I agree with your comment on the 20 gal, too. The W/gal were much better and there was a lot less water for the light to travel through. Especially for the lower plants.

 

[Guest]

Ok, if you have no nitrates and no phosphates and are using RO/DI water in the tank then you can expect some huge algae problems when you add the extra light. Are you adding back into the water anything like Seachem Equilibrium? If not you are harming your fish. They need the dissolved minerals as much as your plants do. Straight RO/DI water is not good for fish. And since it has no buffering capacity it is also subject to huge pH swings. At the very least you will want to cut it with straight tap water.

 

[Spoon]

Interesting...

My local fish guy has me using RO/DI in an effort to keep hair algae under control. (at least that's what I thought) He hasn't mentioned anything about adding back into the water.

Where can I get more info on this?

 

[talenzmeier]

Friendly Advice

By increasing the light intensity, you do run the risk of bigger and better algae blooms. However, if you have a sufficient number of plants, then they will be consuming the CO2 and the other nutrients the algae would want. Since the plants are more complex organisms than algae, they'll consume considerably more resources. With RO water, you need to add something like Kent's RO Right. That will add some of the needed trace elements back into the water. Be sure and make sure your phosphate levels are manageable. Weekly water changes will also help the situation. Another thought is to add peat into your filtration system. This might help too.