Help me figure out why I cant control this green algae!

So if you think it's the rock, what kind of rock is it?

 

I would have guessed it would be 15% water change p/week with tap water but that has been eliminated.

From the pics it looks like the growth is on the left side of the tank, for the most part? I would suggest adding 6-8 Turbos. They will make short work of it...especially if it is a ongoing problem. Judging by your parameters, direct sunlight would also cause that algae. You might consider scrapping off the glass where the algae is growing the most and temp. covering the outside glass with tinfoil for a couple weeks. If it doesn't grow back, you found your problem.

The tank looks awesome BTW!

 

You have a good maintenance schedule. With that much algae you will not see any nitrate or phosphate because it is taking it up before your filtration and chaeto can.

 

What kind of lighting, and how old are your bulbs?

 

Its not the lighting. My bulbs are about 4 months old 150w phoenix 14k. Maybe i should try 20k?

I will be moving my livestock into a new tank in a couple months. I think i will just clean all the rocks in the process and replace all the sand with new sand or clean all the sand as well. I really think its the rock because the rock that has the most algae growing on it has the most cavities for detritus to get into etc.. I try to blast it with powerhead but I'm afraid that doesn't help much. I might need to take it out leave it in a bucket with skimmer running and do 100% water changes every week for a month or so. Have people had to do this before?

Also, how long does it take fish to decompose in tank because i have had fish disappear over 4 months ago and i never found them. Could a dead fish be the source of a lot of phosphate for over 6 months?

 

Its assorted rock, some marshall and a mix of other. 1 piece that has the most algae on it i believe is fiji. Water can flow through the rock and it has many cavities etc...Was probably some kind of hard coral.

 

I think i will add some turbos and astreas to help out. The growth is actually in random places. Most heavily on 1 rock thats high up in middle even though i put the most flow there. I do scrape the algae and suction it off rocks once a week. I think i might try the aluminum foil to see if it will help. I think it might help a little but not much. Thanks for the compliment

 

yup, i should just grow green algae instead of chaeto, lol

 

Do you ever see your Hippo Tang eat any of the algae? Also, instead of doing enormous water changes, I heard Yellow Eyed Tangs are great algae eaters. And if you want to add another species to your CUC, Emerald Crabs do a pretty good job. They can reach into small cavities, at least. And they're almost always eating algae when I look in my tank.

 

go and get yourself three things. first you start with phosphate rx, dose as per instructions.next you start a regime with Algeafix marine, dose as per instructions.
nest you get yourself a sonic brush, kinda like a electric toothbrush that works underwater.any rock you can remove, take out and scrub it under fresh water and replace it. now twice a day use your sonic brush to clean small areas at a time in the tank. dont cloud the whole tank so do small areas. in a week you would have covered most of the tank. dont sit down cause the algea will take over. after you think its under control do a huge water change, 50% and wait a week and do the same again.
make sure your lights are new or replace them. the other big helpers are urchins but they eat right down to bare rock and they especialy love coraline.