Bryopsis Bryopsis is a common problem algae that can overgrow your tank quite quickly. Along with covering your rocks it will also overtake your corals and other desirable algae by outcompeting with them for nutrients. It is generally dark green, coming from the chlorophyts division, and can be either spiky or filamentous (hair like) sometimes misidentified and thought to be caulerpa or debesia, its easy to tell apart by just trying to pluck some off of your rock. Bryopsis tends to burrow deeply into a rock crevice feeding off nutrient rich detritus and thus will take quite a tug to pluck it out.
Contributing Factors There are a few contributing factors to these sudden outbreaks from water quality to lighting. Your nitrates might be too high, your phosphates may be too high (.03 or less is the general goal), your lighting has recently been replaced or perhaps your bulbs are so old that the spectrum of light has shifted, which would bring on this bloom. First thing is first you need to get your water parameters to natural sea water levels:
| Parameter | Level |
|---|
| pH | 8.0 - 8.3 |
| Ammonia | 0 ppm |
| Nitrites | 0 ppm |
| Nitrates | <10ppm |
| Alkalinity | 8-11 dKH |
| Specific Gravity | 1.026 |
| Calcium | 400-450 |
| Phosphate | 0.03 ppm or less. |
A lot of this starts before you even add salt to the water. If you use tap water, your most likely adding nitrates or phosphates to your tank on a daily or weekly basis. RO/DI water is your best and most pure option. Onceyour water parameters are in the acceptable rangeis you need to get the bloom to a manageable level which most of the time means manual extraction (pruning) this process takes some time and consistency on the part of the reefer, you need to keep at this daily to start to get a hold on this green menace. by keeping at this daily and diminishing the amount of algae in the tank your "cleaners" will kick in and help as well (snails, hermits, tangs, etc). Also clean your skimmer completely. The your collection cup often, so you dont have slime buildup hindering it. You want to skim out as much of the dissolved organic compounds before they can break down in your tank and add to the cycle.
You can also introduce algae eaters such as a Lawnmower blenny, Foxface, yellow tang, diadema urchin. Another method of dealing with bryopsis is to go "mechanical" or "non biological" One of the newer trends is the magnesium solution, elevating your magnasium from the normal 1280 ppm to 1500-1600 ppm. Alot of reefers feel this is the least harmful way to correct a bloom. the theory behind this is that the mag stops the photosynthetic processes in the bryopsis, BUT does this without affecting other desirable macros in the reef, but in the same breath some say tha elevated levels can kill desirable inverts, so as with most thing in this hobby, SLOW IS BEST.
You can also try aggressively skimming, elevating your pH to a steady 8.5 for 3 weeks, seems a low ph/alkalinity ratios aggravate an outbreak. Phosphate reactors are also a popular method as well, a more drastic measure would also be taking all of the
LR out of the tank and "cooking" it. I am sure there will be members of the forum that will also chime in on this and add their knowledge and what works for them (that is what these are for, for all of us to learn collectively)
A quick recap of some of the thigs that bring on this dreaded bloom:- adding already "infected" rocks to your tank
- inadequate flow to keep detritus in suspension
- inadequate flow to move detritus through the sytem to the skimmer
- failure to keep detritus off rocks and properly remove from sand bed
- lack of consistent skimming
- poor water source quality (non RO/DI water)
- phosphates are too high
- nitrates too high
- lighting has shifted in spectrum
- new lights
I hope this has shed a little light on the GREEN MONSTER. I said I am SURE that I have over looked something please feel free to add your knowledge and experience in combating this problem.
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