I have a 75g that is 2 years old this week. I have labored successfully over that time to achieve a what was a very stable system through diligence and automation. For the past year up until about 2 months ago, the tank was thriving - algae-wise, just a thin film every few days to scrape off the glass, largely white sand, lots of coralline. I have had small pockets of bubble algae, but emerald crabs keep it in check. Once every 6-9 mos I'd get some cyano or bryopsis that I'd effectively treat with chemi-clean or flux. Otherwise, coral growing like crazy, happy fish.
However, about 2 months ago, something started to shift as I started getting some turfy brown algae, and over the course of a few weeks it turned into fuzzy stuff over every bit of exposed rock and the back wall. It doesn't scrub easily with a tooth brush.
My nutrients fluctuate a bit but have not gotten particularly high. In fact, by most threads here, they're fairly low. I've actually reduced my auto-feeder over the past month by ~2/3. I have a GFO+Carbon reactor that I used to run for 1-2hrs a day to polish and keep PO4 in the .03-.1 range. Lately I've had to crank duration up quite a bit to keep the PO4 down. I can't imagine the source since literally nothing is going into the tank except for 1/3 of the food I used to feed.
All I can imagine is that my biome was effectively consuming / processing what nutrients were going in and now it is not because it can't be an input problem.
In fire fighting mode, over the past few weeks I added a sea hare which is supposed to eat hair algae like crazy and it died after about a week without eating much and I added a lawnmower blenny and he is starving too - so whatever it is - it's not appetizing the the usual algae eaters. It grows like hair algae when left unchecked but the base also feels pretty turfy / like a golf green and as I mentioned, it doesn't scrub easily with a toothbrush. A couple of snails I added ate a bit of it here and there so some are willing to consume.
Right now I'm just trying to really lower my PO4 without bottoming out and things have slowed down and hoping it allows whatever mechanisms were keeping things in check to reestablish but would love any other thoughts.
Here are my nutrients over the past year...
And some pics (algae is hard to photograph!)
However, about 2 months ago, something started to shift as I started getting some turfy brown algae, and over the course of a few weeks it turned into fuzzy stuff over every bit of exposed rock and the back wall. It doesn't scrub easily with a tooth brush.
My nutrients fluctuate a bit but have not gotten particularly high. In fact, by most threads here, they're fairly low. I've actually reduced my auto-feeder over the past month by ~2/3. I have a GFO+Carbon reactor that I used to run for 1-2hrs a day to polish and keep PO4 in the .03-.1 range. Lately I've had to crank duration up quite a bit to keep the PO4 down. I can't imagine the source since literally nothing is going into the tank except for 1/3 of the food I used to feed.
All I can imagine is that my biome was effectively consuming / processing what nutrients were going in and now it is not because it can't be an input problem.
In fire fighting mode, over the past few weeks I added a sea hare which is supposed to eat hair algae like crazy and it died after about a week without eating much and I added a lawnmower blenny and he is starving too - so whatever it is - it's not appetizing the the usual algae eaters. It grows like hair algae when left unchecked but the base also feels pretty turfy / like a golf green and as I mentioned, it doesn't scrub easily with a toothbrush. A couple of snails I added ate a bit of it here and there so some are willing to consume.
Right now I'm just trying to really lower my PO4 without bottoming out and things have slowed down and hoping it allows whatever mechanisms were keeping things in check to reestablish but would love any other thoughts.
Here are my nutrients over the past year...
And some pics (algae is hard to photograph!)
