Corraline algae diminishing on sps tank

[Anonymous]

So, my reef is 2 years old and doing well. I generally had to scrape spots of corraline off the front glass almost every week. Over the summer it just stopped growing. Since then my tuxedo urchin, who previously couldn't make a dent in it has slowly worn through the algae on the tank back and sides.

I haven't scraped a single spot of corraline off my glass since august. The calcium is frequently on the low side, but is high enough to keep the sps growing at an excellent rate. In fact, the sps has started growing particularly fast, probably because I increased the flow in the tank recently. Halimeda does well also.

Is there some other factor in the water that the corraline doesn't like?

 

[liquid]

It could be that your SPS/Halimeda growth is just out pacing the growth of the coralline. Also have you checked your magnesium levels?

Shane

 

[Anonymous]

I don't know how much truth their is, but I have heard the it does not like super bright light.

 

[Anonymous]

Perhaps your nutrients and calcium is now being consumed more by the sps and especially your halimeda. Do you have much more halimeda for instance.?

Just guessing.

 

[Anonymous]

>... don't know how much truth their is, but I have heard the it does not like super bright light.

Yes, there are truth to that.

>...It could be that your SPS/Halimeda growth is just out pacing the growth of the coralline.

Yes, it can be the reason too.

Yes, bob, SPS, halimeda and coralline all compete for the same nutrient, but usually there is no big winner among them.

 

[Anonymous]

My lighting hasn't changed, and I remove halimeda regularly. There is less now than when the corraline was growing well...

 

[ChrisRD]

I agree with Shane - If coralline growth has slowed and you're having trouble maintaining good Ca levels, I'd check on Mg.

Also, some say dosing Strontium really gets the coralline going (maybe you have low Strontium levels?)...

 

[Anonymous]

Hey Chris,

I've never checked the magnesium levels, or strontium either. What are the typical sources for those?

 

[liquid]

[Mg] = 1200-1400 ppm (approx)
[Sr] = 8 ppm (approx)

http://www.advancedaquarist.com/issues/ ... eature.htm

Shane

 

[Anonymous]

Hey Chris,

I've never checked the magnesium levels, or strontium either. What are the typical sources for those?

 

[liquid]

I just posted the levels found in NSW.

Shane

 

[Anonymous]

One other oddity about my tank is that although I've made 3 separate batches of sodium bicarbonate/water mixtures, it still doesn't could my water like it should.

This post by guy:

Freshly mixed Sodium bicarbonate has a relatively high PH. Adding a high PH liquid to a reef tank with a moderate level of Magnesium will cause the Magnesium to temporarily form Magnesium hydroxide. This appears as a cloud. As the local PH drops again the Magnesium hydroxide quickly redissolves.

If that's not happening now then either your Sodium bicarbonate solution was overmixed and CO2 lowered the PH, or it's a weaker solution, or you poured it in slower in a high flow area, or you have a lower Magnesium level.

Suggests, I think, that low magnesium levels will make the mixture not cloud the water.

I have done water changes with fair frequency, but maybe some epsom salts is in order. Actually, maybe I'll get a test kit! Also I've been using Coralife salt, not my choice but all thats been available locally.

 

[ChrisRD]

A lot of hardcore SPS people need to boost Mg occasionally, even though it's in salt mixes and reactor medias. I've used Magnesium Chloride to boost it (when I remember). I've not had a problem with it dropping real fast - usually don't have to mess with it too often. Also, some people throw a little dolomite in their Ca reactor - supposedly that will help maintain it too.

Sr seems to be a similar case - it's there in the salt mixes, reactor medias, etc. but I've heard of plenty of SPS people testing for it regularly and finding their levels low or nonexistent. Some dose Strontium Chloride and claim it really boosts coralline growth. Never tried dosing it personally... ...I hear the test kits are a PITA to use...

I'd start by checking the Mg. I'd loan you a kit but I'm a bit further away these days...

 

[Anonymous]

>...I hear the test kits are a PITA to use...

Dangerous too.

 

[Anonymous]

Thanks! Hey, how did I manage to make a double post 4 minutes apart???

 

[liquid]

Heh, you've got me.

 

[Anonymous]

I am under the impression that some magnesium and strontium is in tap water. And also in food. plus smaller amounts in the crushed oyster shells I use as filter media. Dolimite has magnesium at a certian level or it is called limestone.

Partial water changes with magnesium and strontium at the desired levels will never maintain those levels so long as the aquarium system is increasing or decreasing those levels. All partial water changes will do is delay the rate of increase or decrease of those levels.

 

[Anonymous]

I have done water changes with fair frequency, but maybe some epsom salts is in order. Actually, maybe I'll get a test kit!

Definately do the test kit or you're just blindly dosing. Epsom salts are OK for small adjustments but the sulfate will build up if you dose too much. Dosing Magnesium chloride is better for long term but 10:1 with Epsom salt is a good balanced solution.

Be sure to test first though!

 

[Anonymous]

Seachem makes a good magnesium test kit, it comes with alk included.

Guy, epsom salts? Please tell me how to dose that.

 

[Anonymous]

Guy, epsom salts? Please tell me how to dose that.

Epsom Salt = Magnesium sulfate.

A 1/4 pound of Epsom Salts are required to raise 100 gallons by 25ppm. I wouldn't suggest doing that more that a few times a year.