Fuge Lighting schedule RDP? 24 hrs? Other?

[MarkMal]

I'm building a new fuge in my sump after my hang on the back fuge sprang a leak a while back. I was always under the impression that a lighting schedule opposite of the main tank was ideal for more stable pH but this is a good opportunity to re-examine my assumption. I thought it would be interesting to throw out a poll and get a sense of what most people are doing these days. Thanks!

 

[MnFish1]

I'm building a new fuge in my sump after my hang on the back fuge sprang a leak a while back. I was always under the impression that a lighting schedule opposite of the main tank was ideal for more stable pH but this is a good opportunity to re-examine my assumption. I thought it would be interesting to throw out a poll and get a sense of what most people are doing these days. Thanks!

If I had a fuge again - I would run it opposite to the main display tank. I found them problematic, not worth the trouble - and perhaps counter productive. This will go against the grain for a lot of people - but - to me a refugium is great for keeping fish while they get used to your tank - or just extra space/water volume - but not much else - except possible problems. But - Opposite to the regular tank would be my answer - with a guess that 'it doesnt matter'

 

[MarkMal]

If I had a fuge again - I would run it opposite to the main display tank. I found them problematic, not worth the trouble - and perhaps counter productive. This will go against the grain for a lot of people - but - to me a refugium is great for keeping fish while they get used to your tank - or just extra space/water volume - but not much else - except possible problems. But - Opposite to the regular tank would be my answer - with a guess that 'it doesnt matter'

Thanks for the input. Would you mind sharing why you found them problematic? Might be handy to know what problems you experienced to keep an eye out for something similar. Never had any issues I can think of with my little HOB.... until it popped an acrylic seam and my daughter pointed to the growing puddle on the floor and said, "Daddy, whats that?" Haha.

 

[Dan_P]

I'm building a new fuge in my sump after my hang on the back fuge sprang a leak a while back. I was always under the impression that a lighting schedule opposite of the main tank was ideal for more stable pH but this is a good opportunity to re-examine my assumption. I thought it would be interesting to throw out a poll and get a sense of what most people are doing these days. Thanks!

I have also heard that running the light schedule opposite the tank has benefits. The question that I believe has not been thoroughly addressed is whether a given refugium (I assume you mean an algae scrubber) is large enough to a) boost the oxygen level and b) lower the CO2 at night.

Theoretically it can, but how big would it have to be and what would you measure to size it? What is the ratio of aquarium size and bioload to algae scrubber size? I think most people just think “screw it”, I have so much space and that is the correct size.

There is also the question of light intensity and nitrate and phosphate levels. If your system is low in nitrate and phosphate, the algae scrubber is not going to be photosynthesizing very well and there goes the benefits of oxygen generation and carbon dioxide removal.

Maybe somebody wrote a book to address these design questions.

 

[MarkMal]

I have also heard that running the light schedule opposite the tank has benefits. The question that I believe has not been thoroughly addressed is whether a given refugium (I assume you mean an algae scrubber) is large enough to a) boost the oxygen level and b) lower the CO2 at night.

Theoretically it can, but how big would it have to be and what would you measure to size it? What is the ratio of aquarium size and bioload to algae scrubber size? I think most people just think “screw it”, I have so much space and that is the correct size.

There is also the question of light intensity and nitrate and phosphate levels. If your system is low in nitrate and phosphate, the algae scrubber is not going to be photosynthesizing very well and there goes the benefits of oxygen generation and carbon dioxide removal.

Maybe somebody wrote a book to address these design questions.

Hey Dan! In my case I'm just going with Chaeto in a refugium rather than an actual scrubber but I'm sure all of your musings still apply. My goal is to help reduce/control nitrates with an added benefit of a place for beneficial critters to grow and continually seed the main tank. I'm not necessarily TRYING to affect pH but if I have enough algae to influence the pH I'd rather see it impact the tank in a positive way rather than a negative and if the right lighting schedule potentially makes a difference, than great. It does sound like there is an opportunity to really obsess over the science of it all if that is something one would want to dive deep in too.

 

[MnFish1]

Thanks for the input. Would you mind sharing why you found them problematic? Might be handy to know what problems you experienced to keep an eye out for something similar. Never had any issues I can think of with my little HOB.... until it popped an acrylic seam and my daughter pointed to the growing puddle on the floor and said, "Daddy, whats that?" Haha.

Part of it was that I bought a redsea 750 XXL - which doesnt have a great place to put a large enough one - I did partition it out with eggcrate - etc - and grew chaeto - but there were constant issues with the chaeto escaping, It just didn't seem to be worth the trouble - and I don't miss it. Many people swear by them

 

[Dan_P]

Hey Dan! In my case I'm just going with Chaeto in a refugium rather than an actual scrubber but I'm sure all of your musings still apply. My goal is to help reduce/control nitrates with an added benefit of a place for beneficial critters to grow and continually seed the main tank. I'm not necessarily TRYING to affect pH but if I have enough algae to influence the pH I'd rather see it impact the tank in a positive way rather than a negative and if the right lighting schedule potentially makes a difference, than great. It does sound like there is an opportunity to really obsess over the science of it all if that is something one would want to dive deep in too.

The photo is of a repurposed kitty litter bucket connected to my system. I set it for an order of Ulva. The Ulva delivery was delayed and the bucket went on to become an algae scrubber all by itself. NO3 went to <1 ppm and I need to add PO4 every so often to keep it above 0 ppm (Hanna Checker). I am now feeding the late arriving Ulva to my large Mexican turbos. It is also an amazing refugium. I looked at a small piece of the mat scraped from the wall under a microscope. It was teaming with copepods and worms.

 

[MarkMal]

Dan_P, love the low tech/low cost solution!