new tank

Dear hobby:

Yes, it is not unusual for a microalgae to begin appearing in a new aquarium as it cycles. This usually occurs when the nitrites are cycling and nitrates are beginning to build up in the aquarium. The nitrates are like a nitrogen-based fertilizer for your garden, and high levels of nitrate will fuel the growth of algae.

If the algae is green, this is often a welcome sign in a new aquarium — an indication that nitrites are beginning to accumulate and that the cycling process will be complete before too much longer. So if the algae is a green film that builds up on the aquarium glass or substrate where the light is brightest, that’s nothing to be concerned about. Feel free to clean it away from the viewing surfaces on the aquarium, and if you find it unsightly on your aquarium decor, just leave the aquarium light off while the aquarium cycles and that will control the growth of green algae.

However, other types of algae growth are undesirable, and you will want to remove them or control them as soon as possible. Nuisance algae includes yellow and brown algae (most often due to diatoms), red slime algae (cyanobacteria), and the dreaded hair algae. Hair algae ranges from very dark green to almost black in coloration and is fuzzy in appearance rather than appearing as a film.

If the algae you noticed is yellow or brown then it is most likely due to a bloom of diatoms. They are harmless and most newly set up marine aquariums go through a stage where the diatoms or brown algae grows on surfaces in the aquarium. In most cases, the brown algae will disappear as suddenly as it appeared once it uses up the available supply of some key nutrient in the aquarium (usually silicates). Ordinarily, once the available silica has been exhausted, the population of the diatoms will crash and they will then typically die off on their own. So right now, while your tank is still cycling, you needn’t be concerned if your tank is experiencing a bloom of diatoms — in all probability, that problem will soon solve itself.

Brown diatom algae is usually the first problem algae that a new marine aquarist encounters. A bloom of brown algae often occurs soon after one introduces new live rock to a marine aquarium. This bloom occurs because the curing of the live rock introduces of silicates and nutrients (even pre-cured live rock from your LFS will have some die off after it is transferred to a new aquarium; that’s normal). As a result of the diatom bloom, a brown film soon coats everything inside the tank. Control of brown diatom algae is relatively easy. The first thing to do is to purchase Trochus or Astraea snails that eagerly consume the brown diatom film. I’ve had good results purchasing Trochus snails from IndoPacific Sea Farms (IPSF). There are other snails that will clean the glass such as Nerite and Strombus snails, but Trochus and Astraea snails are the brown diatom cleaner workhorses. If you have your cleanup crew in place, hobby, and it includes Astraea and trocha snails, that will help to get brown algae under control.

Some aquarium scavengers and sanitation engineers are also especially good at eating slime algae or hair algae, so let me know if the algae appears like red slime (cyanobacteria) or fuzzy dark green-to-black hair algae and I can help you to eliminate the undesirable algae.

It’s a good thing that you discovered the salinity on your aquarium was running so high. Gradually reducing the salinity to between 1.024-1.025 may also help control the algae by altering the conditions that it apparently finds favorable for growth. When the time comes, your first seahorses will do best at a salinity of 1.024-1.025.

However, if you already have your cleanup crew in place in your aquarium, be especially careful to lower the salinity very slowly, since many snails cannot tolerate rapid changes in salinity.

Best of luck completing the cycling process for your new aquarium, hobby! Regardless of what type of algae you may have, leaving your aquarium light off while the tank cycles will help to eliminate the algae and dramatically slow its growth.

Respectfully,
Pete Giwojna

Dear hobby:

Your ammonia level is perfect and it appears that your TruVu Aquasystem is cycling nicely, but the nitrite level of 1.00 is still too high to consider installing your cleanup crew at this time. Many invertebrates, including shrimp and some snails, would not tolerate that much nitrite in the water. Here is some more information explaining the acceptable range and optimum level for ammonia and nitrites in a marine aquarium.

Ammonia (NH3/NH4+):
Natural Seawater Value = 0.010 mg/L
Acceptable Range = 0.000 to 0.050 mg/L
Optimum Level = 0 at all times

Ammonia is highly toxic to both fish and invertebrates in even small amounts (> 0.05 mg/L or ppm). Causes of ammonia toxicity include: immature biofilter (new tank syndrome), impairment of the biological filtration due to antibiotics and other medications, overfeeding, overstocking and dead specimens that go undetected (Webber, 2004). Ammonia levels can also rise after the addition of new animals, after a water change, or following a heavy feeding. Any ammonia level above 0.05 mg/L is a cause for concern, and the source must be found and corrected immediately. Be sure to maintain a good schedule of water changes.

Nitrite (N02):
Natural Seawater Value = 0.010 mg/L
Acceptable Range = 0.000 to 0.100 mg/L
Optimum Level = 0 at all times

Nitrite is slightly less poisonous to fishes than ammonia, but deadly to many invertebrates at very small concentrations. Residual levels of nitrite are common in marine aquariums. Levels of 0.05 or less are of little concern in a fish-only aquarium. If the levels are higher than this, the source should be found and corrected immediately. Even trace amounts of nitrite can wreak havoc among the live corals and delicate invertebrates in a reef tank. High levels of nitrite result from the same causes as unacceptable levels of ammonia.

In short, hobby, with a nitrate level of 1.00, you will need to hold off on your cleanup crew for a while longer and deal with the algae growth without the help of herbivorous snails for the time being. Under the circumstances, you can best control the algae growth by reducing the photoperiod in the aquarium and depriving the algae of the light it needs for photosynthesis and growth. Just leave the aquarium light off while your tank finishes cycling and you should be fine.

If the algae growth you are concerned about is a green film on the glass and substrate where the light level is the brightest, then you need not be concerned at this time. Likewise, if the algae growth is brown or yellow-brown, indicating it is probably due to a diatom bloom, that is a fairly normal development for a newly setup marine aquarium and the brown algae normally disappears on its own as the tank matures and the diatoms consume the available silicates in the aquarium and die off. So if the algae is brown, it is again very probably nothing you need to be concerned about at this point.

However, if the algae growth appears as reddish sheets of slime or black slimy sheets, it is most likely due to cyanobacteria and should be eradicated. Likewise, if you are observing hair algae, distinguished by its fuzzy very dark green to black appearance, you will want to take additional measures to eliminate the undesirable nuisance algae.

Best of luck completing the nitrogen cycle and finishing the final preparations of your new seahorse tank, hobby!

Respectfully,
Pete Giwojna