Algae Only Growing on Back Glass

Jmunk

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Tank is over 5 years old now, always struggled with algae issues. Kinda just at my wit's end here. Coral are actually all doing really well and growing (red monti's, few chalices, duncans/frogspawn, leathers, sun corals, acans), and no algae on the rocks almost at all, but algae is all over the back and somewhat side glass.

Here are all the measurements:
Alk: 9dkh
Calc: 430
PO4: 1 - always been high - I'm assuming this is where the problem lies, but I'm not sure the source of it.
Nitrate: 2-3

Side notes:
90G tank - two clownfish, chromis, scopas tang, triggerfish, mag. foxface.
Feeding - I feed twice a day (4PM and 11PM) - each feeding, I do a half a cube and a few minutes of feeding pinches of dry pellets). I know feeding is the most common cause of algae issues. From looking at videos of people like BRS, and even reading posts here, I'm honestly not entirely sure feeding can be entirely blamed, especially for a more established system. It's possible I am way overfeeding though, so let me know.
Window - there IS two windows that shine (especially in the morning) sunlight into the tank. I've heard people say mixed things about the actual effect this can have, but I figured I'd mention it.
Equipment - In the sump, I have a Reef Octopus 200INT skimmer, and one ceramic block.

Any ideas here? Is it just feeding? I'd like to get a refugium but I don't have room in the sump for one at all. Running out of ideas here and I hate looking at an extremely ugly but otherwise healthy and growing tank.
 
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Jmunk

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What kind of rock did you use in your setup, may it be dropping po4
I think that definitely could be a possibility. It's been 5 years so honestly some of the rock I'm not sure about, but I put it live rock, and maybe some of that purple "fake" rock. Funny enough, I added some rock a year or so ago, and it nuked all my xenia and toadstools. No idea how or what happened. I still had algae issues before that, though.
 
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Jmunk

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Do you know what kind of algae it is? That may help narrow your search for a solution.
Not too sure. It just sorta looks like green film algae. Sometimes looks almost like dinos cause I can see some bubbles attached to it. Might just be the air bubbles from the sump running dry. I can take a picture of it tomorrow.
 

Clownfishy

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I have exactly the same issue. I stupidly started with rock from someone elses tank and it was loaded with phosphate. For the first 2 years, I had hair algae on the rock and the back glass. I then did something really silly and used Rowaphos in a reactor and reduced my phosphate down to zero for a long time and then had Dinos! This did greatly reduce the algae from the rocks but not the back glass. I have now moved my Nitrates and Phosphates up to .3ppm and 50ppm (Nitrates) and although I have some algae on the rocks, the main algae grows on the back glass. I have left it to help out compete the Dinos.
In summary, I would suggest buying a Hanna phosphorus checker and keeping your levels low using Rowaphos passively low e.g. 0.03ppm and seeing if that helps. This assume is it a phophate issue but you will be able to confirm that with the Hanna checker. By the way, I used other phosphate test kits but never got a proper reading.
 

reefdude101

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Tank is over 5 years old now, always struggled with algae issues. Kinda just at my wit's end here. Coral are actually all doing really well and growing (red monti's, few chalices, duncans/frogspawn, leathers, sun corals, acans), and no algae on the rocks almost at all, but algae is all over the back and somewhat side glass.

Here are all the measurements:
Alk: 9dkh
Calc: 430
PO4: 1 - always been high - I'm assuming this is where the problem lies, but I'm not sure the source of it.
Nitrate: 2-3

Side notes:
90G tank - two clownfish, chromis, scopas tang, triggerfish, mag. foxface.
Feeding - I feed twice a day (4PM and 11PM) - each feeding, I do a half a cube and a few minutes of feeding pinches of dry pellets). I know feeding is the most common cause of algae issues. From looking at videos of people like BRS, and even reading posts here, I'm honestly not entirely sure feeding can be entirely blamed, especially for a more established system. It's possible I am way overfeeding though, so let me know.
Window - there IS two windows that shine (especially in the morning) sunlight into the tank. I've heard people say mixed things about the actual effect this can have, but I figured I'd mention it.
Equipment - In the sump, I have a Reef Octopus 200INT skimmer, and one ceramic block.

Any ideas here? Is it just feeding? I'd like to get a refugium but I don't have room in the sump for one at all. Running out of ideas here and I hate looking at an extremely ugly but otherwise healthy and growing tank.
Your set up sounds exactly like where I was at

Get yourself a better skimmer I had a 150int biggest piece of junk I’ve ever owned, replaced it with a reefer skimmer 900 the thing is amazing & helps my nutrients a bunch.
Weekly water change.

I think from what I’ve read I can see a lot of nutrient import but no details on what your doing to export these nutrients ?

I also bought a clarisea sk3000.
I did a 100% water change.
Slow your feeding down your over doing it with no nutrient export.
I run nopox & gfo now with a chaeto reactor for night time ph stabilisation, tank is now looking a lot better.

I struggled for two years.
 
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Jmunk

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Your set up sounds exactly like where I was at

Get yourself a better skimmer I had a 150int biggest piece of junk I’ve ever owned, replaced it with a reefer skimmer 900 the thing is amazing & helps my nutrients a bunch.
Weekly water change.

I think from what I’ve read I can see a lot of nutrient import but no details on what your doing to export these nutrients ?

I also bought a clarisea sk3000.
I did a 100% water change.
Slow your feeding down your over doing it with no nutrient export.
I run nopox & gfo now with a chaeto reactor for night time ph stabilisation, tank is now looking a lot better.

I struggled for two years.
I aim to do a water change every 3 weeks or so, around 25 gallons. I also occasionally dose PhosphateRX to bring the numbers down, and while it does work, they obviously go back up. I've even tried daily dosing it in small amounts which DID actually work to maintain my PO4 at a good level. I used to use GFO but hated every single aspect of that tool.

Other than a refugium, I'm not sure what other export tool I can utilize in my tank that would yield better results. I'm all for purchasing something if it's actually going to benefit the tank.
 
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Jmunk

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Here's a picture for those that wanted a visual on what's going on.

IMG_1522.jpg
 
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Mastiffsrule

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Hi @Jmunk

I have been looking at your post for a few days and trying to come up with a good answer. I could come up with anything (nothing new for me :D ) you had not already touched on.

I will throw my experience in for what it is. I put lighting as the issue. I am guessing the light comes thru the window, thru the front pane of the tank and hits the back pane. The back pane reflects the light. That is just a guess, but either way Tank looks great. The pic makes the chromis look bigger than the trigger :D
 

Pistondog

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Tank is over 5 years old now, always struggled with algae issues. Kinda just at my wit's end here. Coral are actually all doing really well and growing (red monti's, few chalices, duncans/frogspawn, leathers, sun corals, acans), and no algae on the rocks almost at all, but algae is all over the back and somewhat side glass.

Here are all the measurements:
Alk: 9dkh
Calc: 430
PO4: 1 - always been high - I'm assuming this is where the problem lies, but I'm not sure the source of it.
Nitrate: 2-3

Side notes:
90G tank - two clownfish, chromis, scopas tang, triggerfish, mag. foxface.
Feeding - I feed twice a day (4PM and 11PM) - each feeding, I do a half a cube and a few minutes of feeding pinches of dry pellets). I know feeding is the most common cause of algae issues. From looking at videos of people like BRS, and even reading posts here, I'm honestly not entirely sure feeding can be entirely blamed, especially for a more established system. It's possible I am way overfeeding though, so let me know.
Window - there IS two windows that shine (especially in the morning) sunlight into the tank. I've heard people say mixed things about the actual effect this can have, but I figured I'd mention it.
Equipment - In the sump, I have a Reef Octopus 200INT skimmer, and one ceramic block.

Any ideas here? Is it just feeding? I'd like to get a refugium but I don't have room in the sump for one at all. Running out of ideas here and I hate looking at an extremely ugly but otherwise healthy and growing tank.
No mixed feelings about sunshine, it will cause algea. Can you block the tank rear with card board or other.

Reef roids and nori will cause phosphates.
 
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Jmunk

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Hi @Jmunk

I have been looking at your post for a few days and trying to come up with a good answer. I could come up with anything (nothing new for me :D ) you had not already touched on.

I will throw my experience in for what it is. I put lighting as the issue. I am guessing the light comes thru the window, thru the front pane of the tank and hits the back pane. The back pane reflects the light. That is just a guess, but either way Tank looks great. The pic makes the chromis look bigger than the trigger :D
Haha, he sure is getting big!
 
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Jmunk

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No mixed feelings about sunshine, it will cause algea. Can you block the tank rear with card board or other.

Reef roids and nori will cause phosphates.
Isn't there though? I've seen stuff on forums before about that topic and (while I'm not sure who's right), a lot have people have said window light won't make a difference. After all, we are trying to emulate the sun. I wonder, would just some black cardboard on the back glass make a difference, though, if the light is still getting in?
 

Pistondog

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Isn't there though? I've seen stuff on forums before about that topic and (while I'm not sure who's right), a lot have people have said window light won't make a difference. After all, we are trying to emulate the sun. I wonder, would just some black cardboard on the back glass make a difference, though, if the light is still getting in?
Doesn't seems like much effort to run an experiment with a piece of cardboard for a few months.
All we can do is use our own sense to filter opinions and decide on some action.
I have a skylight that this time of year that hits the tank for an hour. I have to block with an umbrella, or algae.
I run this experiment every day for 6 weeks. If I forget the umbrella, there is no opinion discussion, there is algae.
You are correct it will not do any good if you do not reduce the sunlight effectively.
Most will not locate a tank near a window for this reason.
Snails might help lessen the frequency of window scraping.
Glad it is not bothering your corals, in fact you might find some corals prefer sunlight to artificial.
Try some brigntwell aquatics phosphat-e cautiously to help lower the high phosphate, which is also contributing to algae growth.
Good luck.
 
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