brown algae/cyano problem

[jon_denmark]

Hi
My tank have been running for 1 year. After the tank has cycled, i've got lots of calciurous algers. During the summer the temperature raised to about 28-29 degree celcius for a short period of time. The temperature are now back to normal but i have got lots of brown algae covering most of the substrate. The algae problem started out as large areas of red slime algae. These are know gone and brown ones has taken over. When there has been light on the tank for about 1-2 hours the algae develop lots of bubbles, making the tank look like when it is snowing (just turned around). I can't measure any NO3 or PO4 and i use rewerse osmosis for my water changes. My calcium reactor have only been running for a week now, and i hope that it will help to raise my carbonate-hardness (don't know if this is the name in english :? ), in order to buffer up the ph-value. At the moment the ph-value varies between 7.8 and 8.0.
I now that the brown algear are covering houndreds of species but maybe you do have some tricks i could learn by. Please post questions, and idears and i will try to go in to more details with my setup.

Best regards, Jon

 

[Len]

Hey Jon!

What you're describing is dinoflagellates from what I can tell. Unlike diatoms, dinos have a tendancy to trap air bubbles in mucus-like strings. The usual recommendation to get rid of dinoflagellates is to elevate pH (yours is on the low side). Buffering the carbonate hardness will help maintain pH levels (Ca reactors do a good job at this), but it doesn't really elevate pH levels. What I recommend you do is to drip kalkwasser in addition to your Ca reactor to bring up the pH while maintaining high Ca and alkanity levels. There are chemicals that can kill dinoflagellates, but I don't recommend them since zooxanthallae (the symbiotic algae in corals) are dinoflagellates.

If the algae is diatoms, you may want to try a silicate sponge. Since you use R/O and have a nice skimmer, I'm not sure where these algaes are getting their nutrients from. If it's a relatively new tank, that would explain a lot. These types of algae blooms are natural for immature tanks, and they tend to go away as the tank ages.

 

[jon_denmark]

Hi Len
Your description of dinoflagellates fits perfectly. Actually there are several of the strings containing bubbles as you descripe. I am very interested in learning more about dinoflagellates, so if you know any web adresses covering the issue please post
My calcium reactor have not been able to increase the ph the week it has been running. The kh in the outled are 30 (germen kh-degrees), and the ph in the reactor is 6,25. I have thought of getting a media called ARM wich dissolves at a ph value of as much as 7,5. With this media I should easily get a kh of 50 in the outled without having to lower the ph to under 7.

 

[Anonymous]

Your Ph sounds awfully low for a reef tank....correct if im wrong Len but 7.8....i would probably like to see it 8.2 at least...

 

[Anonymous]

Ditto....I like to keep mt Ph at least 8.0...and even that is on the low side.

 

[jon_denmark]

The reason why my ph value are only 7,8-8,0 i think is that the kh-buffer are only 6. Tomorow i will go and get some "kalkwasser" which i hope will increase the ph. As far as i know the kh and calcium-content usually follow each other. In my case the calcium are 550 and the kh=6. Actually the water comming out the calciumreactor has a calcium consentration of ~ 420. I have done the tests twice and are a bit confused because of these strange readings. The kh, on they other hand, coming out the reactor are close to 35.

 

[Anonymous]

Whoa, id first go with a ph buffer, and slowly add it, like day by day, until its around 8.2....then periodically add it to maintain it...my water here in nevada is high ph wise, so i works out for me...however the water is hard and high in nutrients..drawback..bummer

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