I would have my doubts , how small of water volume are we talking? Rock can only leach phosphates for so long it's not something that is created long term and if you acid bathed the rock then its surface has been stripped clean. How do you export nutrients now and when did you start with phosphate removers?

It's not just nitrates and phosphates that algae uses but other elements as well, and some algaes are tolerant of low nutrient conditions so as the saying goes know your enemy to find his weaknesses ....basically I.D the algae

A pic would help :)

Also fwiw , gha is not a phase that you have to go through its certainly not a guarantee regardless of the type of rock you use so at the point of gha you should be asking yourself what's missing here? It all comes down to access to nutrients .......who has access to them first and what they do with them and what I or you can do to use this to my advantage ;)

Manipulating how nutrients are used and exported can be one of the most useful tools in keeping a healthy reef be it to keep away pest algaes or to overall improve animal health.

Should I go with an 11oz bag of Chemi-Pure Elite?
Not sure what GFO is?

Gfo is a tupe of phosphate remover and chemipure is a mix of carbon and gfo in one:) the 11oz bad of chemipure should be fine its mostly carbon anyways :)

The algae is green hair algae, its a 70gallon tank with a 30 gallon sump. For nutrient export i am using sro 1000 protein skimmer and been doin 10 gallon water changes a week. i am using phosban in one reactor and carbon in another that was started about a month ago. im not saying bad about the rock. i love the rock, most amazing looking rock ive ever seen, but heard it could be a reason with algae probs in other peoples posts. got 3 chromis and lawn mower blenny and all kinds of snails and a few small hermits. been feeding mysis and pellets but not overfeeding. so i dont know what could be driving it

I thought that just as diatoms is one stage, that gha came next in succession but should fade in time. And to think i was happy to see the diatoms (finally something happening). If the gha is hogging all nutrients (like nitrate) im worried that any anaerobic bacteria wont have a chance to grow and that nitrates would always be avail to gha first and therefore the gha support it self in an on going cycle. I dont know where the nutrients are coming from, it was happening even before the cuc.

No it's not , green hair algae is certainly something that you don't wait for or ride out and has absolutely nothing to do with the nitrogen cycle , if your phosphates manage to get to 1.6 the you allowed the nutrients to control you and gave the algae a food source , you waited too long before taking action. a great tip is its easier to prevent then it is to remove

I'll use my own system as a perfect example , this system does the opposite of what most reefers will tell you what to do , it's loaded with don't do this or you'll end up with that's... Going by the rules of reefing I should have a nutrient soup of pests but I don't in fact I have a purely algae free system , loaded with corals and fish , rock is Coraline covered and an abundance of sponges and feather dusters all over the tank and this system is around 10mths old.you'd be hard pressed to find a white spot of anything anywhere in the tank it's packed in full.

My recipe for disaster:

Tap water
No live rock
All pukani
No acid or bleach
No cure
No live sand


So why is my system running perfectly and how did I go around all this?

I manipulated the nutrients as I needed them , I first stripped the system bare and added what I needed when I needed it and removed anything I didn't ......it's that simple I didn't jump on the boat and go for a ride I hopped my own boat and drove exactly where I needed to go :)

Where's the fun in that?? lol But ya, proactively having a plan and implementing it is the correct course. Reacting to stuff is a poor backup plan.

Like Albert said in another thread about the shrimp , traditionally we add fish or something slowly rotting to get an ammonia source but among other things as well , if we want ammonia then add amonia directly , it's a great example of having the option to manipulate this to your advantage you have the power to add and take it away and therefore you have control if you choose to use it :)