View Full Version : Help with GHA

07/22/2015, 01:52 PM
So this is a new 75G tank... not quite a month old and I'm starting to get a bit of GHA on some of the rockwork. It's definitely not taking over the tank at this point... it's maybe on 5% of the rockwork now, but it's definitely been slowly increasing over the past two weeks or so... I started seeing one or two small patches about two weeks ago.

Phosphates seem low (about .5ppm) and nitrates are at about 40ppm. The tank was filled with RO (but not RODI) water and I just started changing about 1G/day of water. I checked the new water and it was showing 0ppm phosphates.

Do you think it'll just run it's course if I let it go or is it more likely to take over the tank? Would I be better off trying to remove as much I can with a toothbrush to help speed up the process or is that more likely to cause it to spread? Like I said, at this point the tank is mostly GHA free except for a few reasonably isolated spots.

07/22/2015, 02:01 PM
Start running GFO

07/22/2015, 02:14 PM
Start running GFO

+1 and get some snails...

07/22/2015, 02:33 PM
Short term, use API's AlgaeFix Marine. It will kill off the hair algae in short order with no ill affects. Here is a thread about it on RC -


Long term, invest in an ATS (Algae Turf Scrubber) and don't look back. Grow the hair algae where you want to, to naturally remove excessive nutrients. It will out compete the display tank's hair algae and it will disappear, and you can run your tank as normal.

Here is a good thread read in the Advanced section on RC -


Here is a pic of one of mine, that is on my 150g -

07/22/2015, 02:42 PM
You'll want your phosphates under .1 and ideally under .08. Nitrates I target to get under 10 which usually comes up as undetectable on API test kits.

Here's a good thread on GHA removal. Patience is needed. I would not use the AlgaeFix unless it's absolutely necessary. Same as raising Mg to very high levels.


07/22/2015, 04:24 PM
Thanks guys. I was looking at phosban and I noticed that it also removes silicates... I have several sponges in the tank, so I'm worried about removing silicates (the sponges weren't my choice... They came with the live rock, but now that they're there I'd rather not lose them).

The ATS definitely looks like an interesting option.