Nuisance Algae to Nutrients Ratio

[ErehwoN]

I have a 125g reef tank that had a serious problem with nuisance algae. Turf, hair and bubble algae were the latest problems. Much of the advice suggests lowering nutrients to combat the algae. Just prior to making the changes below, my nitrates were at 0 and phosphates were at 0.04, per Red Sea test kits.

Because I was negligent in dealing with the algae early, I had to admit defeat on several of the large pieces of rock as they were thickly coated with the algae and only way to get ahead would be with physical removal. I had extra rock so I removed the ugly algae rock and replaced it with clean, dry rock.

So, given that all other things remained equal, here's my question: With the removal of the vast majority of the nuisance algae, shouldn't my nutrients spike? Stated another way, if lowering nutrients is the key to starving out algae, shouldn't the elimination of the algae mean that fewer nutrients are consumed resulting in more in the water?

I understand there are other factors, including the removal of biome in favor of sterile surfaces, or the possibility of triggering another cycle, but shouldn't I see some difference, especially in the short term?

Thoughts and comments appreciated.

Jim

 

[Randy Holmes-Farley]

I do not agree that reducing nutrients to deter algae is a good strategy. It typically fails because nutrients have to be low enough to also stress corals unless you provide them with N and P in other ways, such as particulate foods, amino acids, etc.

Herbivores are usually a better bet.

 

[killer2001]

Agreed. Keep the nutrients up, dose silica to promote diatom bloom, manual removal, and herbivores have all worked for me.

 

[ReeferFive-0]

The hobby is moving away from lowering nutrients to starve out algae. Zero nitrate or phosphate is asking for problems, as corals need some of these in the water. Keeping things balanced is key, such as nitrates at 0.1 ppm or under (not zero) and phosphates at a slightly higher concentration than phosphate, some say 10 to 1 nitrate/phosphate ratio is ideal. In the future, you'll want to consider scrubbing the live rock of algae and returning it to the tank, as replacing it will reduce the good bacteria you need in the system. Proper parameters, flow, and a good clean up crew are important components of a reef aquarium.

 

[ErehwoN]

I do not agree that reducing nutrients to deter algae is a good strategy. It typically fails because nutrients have to be low enough to also stress corals unless you provide them with N and P in other ways, such as particulate foods, amino acids, etc.

Herbivores are usually a better bet.

Agreed. Keep the nutrients up, dose silica to promote diatom bloom, manual removal, and herbivores have all worked for me.

The hobby is moving away from lowering nutrients to starve out algae. Zero nitrate or phosphate is asking for problems, as corals need some of these in the water. Keeping things balanced is key, such as nitrates at 0.1 ppm or under (not zero) and phosphates at a slightly higher concentration than phosphate, some say 10 to 1 nitrate/phosphate ratio is ideal. In the future, you'll want to consider scrubbing the live rock of algae and returning it to the tank, as replacing it will reduce the good bacteria you need in the system. Proper parameters, flow, and a good clean up crew are important components of a reef aquarium.

And I agree as well. I understand the importance of the nutrients. I didn't want to start down that discussion with this thread because raising nitrates in my case is important going forward. But I'm asking if my results support the idea of lower nutrients NOT being a primary factor in fighting algae since the removal of a large amount of algae didn't result in noticeably higher nutrients?

Jim

 

[Randy Holmes-Farley]

And I agree as well. I understand the importance of the nutrients. I didn't want to start down that discussion with this thread because raising nitrates in my case is important going forward. But I'm asking if my results support the idea of lower nutrients NOT being a primary factor in fighting algae since the removal of a large amount of algae didn't result in noticeably higher nutrients?

Jim

How long has it been since removing the algae? Perhaps waiting longer will show more effect.

Lots of it does not necessarily mean it is growing a lot faster than after removing some.

Think of hair. It isn’t necessarily growing faster when it is long vs short in the same person. I know it’s not a perfect analogy, but short cropped algae can still grow.

 

[ErehwoN]

How long has it been since removing the algae? Perhaps waiting longer will show more effect.

Lots of it does not necessarily mean it is growing a lot faster than after removing some.

Think of hair. It isn’t necessarily growing faster when it is long vs short in the same person. I know it’s not a perfect analogy, but short cropped algae can still grow.

It has only been two weeks. I like the hair analogy and I'm going to add to it. If my tank had 6 overrun pieces of live rock, and I remove 4, isn't that the same as removing 4 heads of hair from 6? The algae on those rocks wasn't shortened, the entire rock with the algae was removed. Thus the remaining algae growing is only 33 1/3% of the original amount. I fully expected some parameter swing but so far, nothing.

 

[Randy Holmes-Farley]

It has only been two weeks. I like the hair analogy and I'm going to add to it. If my tank had 6 overrun pieces of live rock, and I remove 4, isn't that the same as removing 4 heads of hair from 6? The algae on those rocks wasn't shortened, the entire rock with the algae was removed. Thus the remaining algae growing is only 33 1/3% of the original amount. I fully expected some parameter swing but so far, nothing.

Depends on what is under the removed rocks and whether algae begins to grow there on surfaces newly exposed to light, but I understand your point.