Reef chemistry and nuisance algae

[Kristy]

Okay, I need to take the special ed class on reef chemistry because I seem to learn it very s-l-o-w-l-y. (Seriously if someone taught "reef chemistry for dummies," I would pay to attend!)

We struggle now and then with slight cyano issues (or a variation of cyano that seems to be a bit different) due to a healthy fish load and heavy feeding, among other sins. We also have bouts of another algae that I have never seen in anyone else's tank, a very slow growing leathery algae (brown to olive green) that you can peel right off the rocks, only shows up in a couple of isolated spots.

Last week I returned from six weeks out of town to find that Mike is not nearly as attentive a cleaner as I am. This combined with his love of overfeeding led to some swampy algae conditions we've NEVER encountered before. A 30% water change with some aggressive scrubbing had the tank looking much, much better but I am keeping a close eye on the algae growth. There is still some cyano but not much and it is clearly receding, still some leathery stuff, but that too is going away. Now I notice a new algae, best description is red hair algae, that is beginning to creep onto a few spots.

I am fighting it the best I can with manual removal and we will do another good water change this weekend. In the meantime, I could use a refresher about the reef chemistry issues that contribute to nuisance algae...

What do I want to be monitoring? What should our goals be as far as reef chemistry goes here (reduce phosphates, for example) and what is your best recommendation on how to achieve this?

We do have a sump that grows macro at a healthy rate, by the way.

[Bill S]

Well, I'm not one to ask about this - since you've seen my bryopsis problem.

Yours sounds pretty much like an overfeeding issue, that SHOULD sort itself out with water changes, less feeding, skimming and good circulation.

What is your cleanup crew like? You have a BIG tank, it should have 1000 or so in it...

IF you can keep your pH above 8.4, that tends to discourage many algaes.

[Kristy]

Actually, Bill, I'd say you're JUST the one to ask about this, because I know you have given it a ton of thought and knowledge!

We'll keep up the escalated water change schedule and get the feedings back under control to see if that takes care of it. We have recently taken some measures to improve circulation, so I think that is good, but we keep saying we need to keep an eye out for a better skimmer if the right one presents itself. Ours is probably not up to the load we have.

The pH is a good idea... I can usually keep it about 8.2 but it has dropped to 8.0 so I was going to drip kalk today to get it back up. If 8.4 will do the trick then we'll do our best to get it there. My understanding is that I drip kalk to get it up where I need it and then B-Ionic 2 part will keep it balanced up there? Is that right?

[Joshua]

A lot of people who struggle with algae are topping off with water that is either knowingly or unknowingly poor quality, when this happens water changes don't even seem to help much because you're still just adding poor water in. If you're buying water somewhere have it tested or try a new source. If you have an RO/DI change all the filters, or if the TDS is really low skip the DI step and try straight RO for a week or two. I had some terrible problems for about 6 months with 0 TDS coming out of my RO/DI and it turns out my DI was leaching something into the water and as soon as I skipped it the algae began dieing off.

[Kristy]

Thanks so much for the great tips Joshua and Bill! I had not even thought about the relationship, but we do need to do a filter change on the RO/DI. You are giving me some good solid hope.

Any other thoughts about what might need to be monitored?