macro-algae dying

[Harry]

I've been very careful not to overfeed my shrimp; I feed a flake or two every two weeks. My glass is very clear, but I do see dots of algae forming on it when I look with a magnifier. And the shrimp seem to feed off the glass. But much of my macro-algae has turned yellow. I suspect that there may not be enough nutrients in the water. I tossed most of the yellow stuff. Should I be feeding more regularly. I've had the tanks since January and no offspring so far.

[Rob in Puyallup]

Hi Harry,

How's the lighting in your tank?

A bit of food is good for the shrimp and the macroalgae.

[Harry]

The lighting is good. I have a combo fluorescent/incandescent lamp on a timer. It's designed to simulate daylight. The water is very clear and the shrimp are fine. I tossed the yellow macro-algae and we'll see how the remaining algae fares.

[Mustafa]

I agree with Rob. You should increase the amount you feed by say....twice? Keep the same frequency. If you're barely getting any biofilm to grow on the glass, then there are obviously not enough nutrients going into the system. Ideally, you should get to a point, where three sides of the tank should have clearly visible algae covering (not thick coverings...thin), and you just keep the front pane clean for viewing. Your macroalgae will start growing at that point, too. This species of macroalga does not need much in terms of nutrients at all, but it needs a bare minimum. Don't worry, though..once the conditions are right, even a tiny string of it can take over your whole tank...slowly...given time.

You're in the rare camp of people that has an actual *good* problem. If you have a overfeeding problem, you may upset the tank's balance and kill the shrimp. If you underfeed, you're only problems are lack of macroalgae growth and lack of breeding. So, breeding should start within several months of increased biofilm/surface algae growth.

[Harry]

Great news! I've been neglecting the two tanks, as I thought this was the thing to do. I'll start a regular feeding cycle of a flake or two twice a week.

[Mustafa]

No..no...no....Not sure if you just didn't see it, but read the first sentence I wrote above again:

You should increase the amount you feed by say....twice? Keep the same frequency.

So...just increase the amount you feed, but still feed every two weeks. That way, if you end up overfeeding (which you will eventually), your tank has two weeks to "absorb" it. Plus, you'll have two weeks to observe if algae growth is increasing. The trick is not "neglecting" the tank, it's to have a regular 2-3 week feeding schedule. You just have to vary the amount you feed according to what's happening in your tank.