Tyrone Genade

I ran my 60 gal (120 x 45 x 50 cm) with 2 40W tubes for years getting excellent plant growth. At first it was with the Phillips New Generation Flutone (which are like natural daylight) and later, because I was cheap, with plain cool whites. Plants grew well. My pygmy chain swords at a depth of 45 cm were nice and red and running rampant.

As you are using Gro-lux tubes which peak in the red you should do even better. I have 3x 30W tubes over the same tank at this moment: 1 Grolux and 2 Aquastars. The HM growing under the Grolux grows horizontal while those directly under the Aquastars are growing straight up in search of more light. Under the Grolux and at depth of 45 cm the Riccia pearls. I have Cabomba in the tank and it grows like a weed.

Instead of the 2nd Grolux, rather go with a Triton, GE Aqua Rays or something which is more full spectrum (like Biolux) or like daylight so you can balance out the Grolux which look pale and look more red and blue rather than green.

Best of luck HVS.

Dustymac

Here's an update after six weeks...

In the 55 gallon NPT, the one which gets some sunlight, there was one significant change after initiating a 4-hour afternoon siesta: the Corys stopped spawning completely. Plant and algae growth seem about the same as far as I can tell. Ten days ago I stopped the siesta and the Corys started spawning again. Weird.

Even more weird, in the 45 gallon which gets little to no sunlight and has the same siesta, some three year old Black-lined Tetras started showing some preliminary spawning behavior. That lasted for a week but now it's business as usual. Plant and algae growth are also about the same and that tank is still getting a siesta. So, I'm saving energy on one of the two tanks.

Jim

trag

I don't know if it's relevant, but my corys always spawn at dawn and a little after. Perhaps having two photoperiods confuses them?

In response to the much earlier post from the fellow who asked about having several siestas in the day: I don't know what it would do for or against plant growth, but it would be terrible for your lights. The hourly rating on fluorescent and metal halide lights assumes a certain number of hours of continuously on operation (at least 3 hours). If you use shorter 'on' periods than that, then you are turning the lights on and off more often than the specification considers and your light bulb life will be shortened to less than the published bulb specification.

In other words, turning your lights on and off shortens the light bulbs' lives. It's probably worth it for one siesta per day. More than one...well I guess it's a personal decision based on your pocket book.

Using the siesta method certainly seems to reduce algae in my tanks. I have two 39 watt 6500K T5 HO bulbs on each 30 gallon (12" X 36") tank and without the siesta algae gets to be a problem. It's still an annoyance, but it's not threatening to crawl out and eat Tokyo.

dwalstad

Theoretically, the Siesta can help plants better compete with algae in the afternoon (lights come on after CO2 has had a chance to build up a little). It may not help control algae in every situation, but I'm glad to hear that it helps in yours.

Thanks for writing!