But, sigh, it seems like they're being replaced by GHA. There's obviously excess nutrients in the tank but I'm not sure what the cause is. I use distilled water for water changes. I only feed my fish once a day with some pellets (I feed 1-2 to reduce wasted food); a capful of marine snow once a week for the corals. Occasionally I'll feed some mysis shrimp as a treat. I change 2g of water a week (in a 20g tank). And like I said, I've added some red mangroves/Purigen to soak up some excess nutrients. I also have chemipure (containing GFO) in the media basket. Also, my bioload is pretty small. I have a couple of corals, a pretty standard clean up crew (about 12 medium size snails + 20 dwarf ceriths + medium size hermit + 1 peppermint shrimp), and a pair of small (~1.25" each) ocellaris clownfish. I am not running a skimmer.
My tank is over 2.5 months old, which is obviously still pretty young. Is this a phase that young tanks go through (like with diatoms)? Or do I have a real problem with nutrient export? I had a few options in mind:
1. Do nothing. Just let the algae run its course and wait it out. Keep up with water changes and be careful not to overfeed.
2. Add some more CUC that specialize in GHA like 1-2 hermits, or an emerald crab. The downside to this is that I would be adding more to the bioload.
3. Increase frequency and/or size of water changes
4. Add some macroalgae to go along with the mangroves. I'm thinking about throwing a ball of chaeto into the display to compete with undesirable algae.
If anyone can suggest which of these options, or which combination of options above would be the best course of action, I would appreciate it. Thanks!