I’m using RO water. It’s a 30 gallon JBJ nanotank. I didn’t test parameters this time but I always do. Every time I test it’s always normal. I don’t see anything out of the ordinary or nutrients out of whack. I have green algae on the rocks which I find normal. But it starts to grow into green hair algae. The sands starts to grow on it too. Every month or 2, I have to just scoop up the algae and throw the sand away. It’s like it clumps all together. But it’s green. My snails seems to be uninterested and my black urchin seems to be confused. My tank is a year and six months. 8 months into it I had to reset or restart due to a horrible aiptasia outbreak. That time I used rock that was already cycled. This time I used dry rock and it’s been a battle. And my coral, it doesn’t grow. It’s just there. I use Red Sea coral pro salt and always mix it to 1.024 to 1.027. I let it even out in the tank with my ATO. I have the tank at about 76 to 78 degrees.
Lighting is not necessarily the sole reason.
However do drop your reds and greens and whites way low to like 30% keep your blues up way higher.
What corals do you have stocked? As funny as it sounds without something fighting the Algae for Nutrients, it's going to keep coming back no matter what you do. If there's NOTHING growing in the tank, and it 's healthy, Algae will find a way to grow, I think it would be impossible to completely remove all Algae spores from a reef tank. Are you dosing any Cal and Mag for your corals? they need that to grow as well, and once they grow they will then use up other nutrients, it's kind of like if you don't have protein and carbs but just protein or just carbs you can't work like that.
If you have great bio-diversity , and you're dosing Cal and Mag, you still have options, you can try exchanging and switching up your CUC. Do you have any hermits? my Hermits love GHA. Emerald Crabs are also good Algae eaters.
Try Scarlet, or Blue Legs.
Otherwise you could do a weekend long project, of seperating everything out, really scrubbing it down outside the tank, doing 50% water change of tank water, after stirring up the detritus in the sand and letting it run through the filter floss and other filter media for a little bit.
i.e. Take all the rock and corals out into a
Plastic Bin or something like this you can buy at home depot or something for cheap. with about 10G of water.
If you can't easily remove the coral from the rock, then leave it on, but scrub all the rock with a tooth brush in that water and get all the algae off in the bucket. Rinse the rocks off in the bucket of water by swishing them around.
Then go to the tank and try to syphon out as much Algae as you can out, You can use a little tip electric taped at the end to agitate the sand. Or just vaccuum it up into the tube, and use the pinching method to stop the siphon let all the sand fall down, while the detritus stays floating, and then un-pinch and let the detritus flow out.
That coupled with doing some other things like the above will probably help you get it completely beaten within a month or so.
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If you don't want to do that long project, by addressing a few points above, (If you haven't already done all of them) then you can should try it and hopefully see improvements and then hopefully termination in a few months.
Bio Diversity handled this in one of my tanks. I didn't have to do anything else but just add more bio-diversity and Hermits.
Also what's your feeding schedule like? In Nano's and tanks 50G and under, I've found EVERY OTHER DAY FEEDING is like a god send.
Lastly, as a final effort.
You can try non-natural methods like Vibrant coupled with a UV sterilzer half way through the week. I'm almost positive that will handle it.
(i.e. Dose Vibrant, let it do it's thing for 3-4 days, then UV Sterlizer until next dose at 7 days)
