High Nutrient Macro Algae/Sea Grass Reef

[vlangel]

Today I manually removed algae from the blades of shoal seagrass. I also removed a lot of feather caulerpa. My nitrates are low so my theory is that the macro algaes (specifically the feather caulerpa which is growing at a phenomenal rate) is sucking up almost all the nutrients which is why there is some cyano in the fuge. Getting just the right amount of nutrients put into the tank via fish food/wastes versus uptake of those nutrients by coral, seagrass and macro algae is going to be tricky. I have filter feeders like feather dusters and scallops that absolutely need nutrients in the water column plus the coral, seagrass, and macro algae. It's a fun challenge however.

 

[vlangel]

https://youtu.be/OOTDie0J5B0
A closer look at the display tank in more detail during a feeding.

 

[Michael Hoaster]

I agree, Dawn, the caulepras are piggies. The bigger they get, the more nutrients they use. Good idea on the aggressive export.

When you clean the grasses, are the roots holding them in place? I found it to be no biggie if I pulled them up to remove algae, but if the roots hold it's a good sign.

You've obviously given yourself a challenge, keeping such a diverse community. It's doing incredibly well, so I'd say you're up for it! Fine tuning's expected with the recent system and fish changes.

 

[vlangel]

I agree, Dawn, the caulepras are piggies. The bigger they get, the more nutrients they use. Good idea on the aggressive export.

When you clean the grasses, are the roots holding them in place? I found it to be no biggie if I pulled them up to remove algae, but if the roots hold it's a good sign.

You've obviously given yourself a challenge, keeping such a diverse community. It's doing incredibly well, so I'd say you're up for it! Fine tuning's expected with the recent system and fish changes.

Thank you for sharing your experience with caulerpa and its uptake of of nutrients. That is encouraging to me.

My shoal seagrass does appear rooted. I thought that seemed like a good sign too. I really appreciate you sharing that. In general I think the seagrass is doing well. Thank you!

 

[Michael Hoaster]

Yay! That's great to hear. Rock on!

 

[vlangel]

Wow, tonight while I was feeding frozen to the display, guess who I saw? Cheerleader my pom pom crab! I can not even remember when the last time I spotted him, probably a year or more ago. He looked great too. That was so cool to know that he is happily living in this tank so full of creatures.

 

[Michael Hoaster]

That's so cool! Woo!

 

[vlangel]

This morning I added a little more sugar oolite sand to my refugium. I had removed this sand from a remote DSB I had in the sump. With the addition of the 30g refugium I decided that the compartment for a fuge in the sump was unnecessary so I removed the DSB and the partition between it and the return pump. That allows the return pump to sit on the floor of the sump and not suck air as soon due to evaporation.

Anyway, while I was adding a cupful of sand I spent some time studying the grass shrimp. I would guess about a fifth of them were berried which is exciting. Surely some of those hatched larvae find their way to the display to be live food for the fish and coral. All 3 peppermint shrimp are still in the fuge as well. Hopefully they are reproducing too.

The only thing I am not pleased about is the carpenter wrasse being in the fuge. He is probably eating the pods and larvae almost to extinction. He is such a scaredy cat fish though. He hides over nothing, so I do not see him doing well in the display. I could move him to the sump or maybe it would be best to just rehome him.

 

[Michael Hoaster]

That's funny, Dawn, I'm considering adding sand to my display. The cyanobacteria I have is on the sand bed, and while I got a lot of it, I'm tempted to cover up what remains. But in my experience, it's a very temporary solution. So I'll wait on adding sand for now, and see what else needs to be done.

That's pretty neat keeping those grass shrimp alive and reproducing! I agree the wrasse defeats the purpose. Will your LFS give you store credit for it?

 

[vlangel]

That's funny, Dawn, I'm considering adding sand to my display. The cyanobacteria I have is on the sand bed, and while I got a lot of it, I'm tempted to cover up what remains. But in my experience, it's a very temporary solution. So I'll wait on adding sand for now, and see what else needs to be done.

That's pretty neat keeping those grass shrimp alive and reproducing! I agree the wrasse defeats the purpose. Will your LFS give you store credit for it?

I hear ya about adding sand only being a temporary solution to cyano as that has been my experience as well. That was not my reason for adding it. I just want a deeper sandbed is all. Also it is a fine oolite which will help with maintaining PH as it dissolves. I only add a little at a time because I know too much on top smothers and kills the aerobic bacteria on the sandbed surface. I learned that in the days when I maintenanced tanks and caused a major ammonia spike. Once is learning but I never repeated the mistake.

I am excited about the grass shrimp. They were left overs from when I was feeding Samson, my last seahorse. I am sure that they are appreciative of their new role for my hobby, ha ha!
One of my LFS may give me credit, I am not sure.

 

[vlangel]

A late afternoon pic when the sun is low enough on the horizon to shine in the window on the tank for about half an hour. I thought it was pretty.

 

[Michael Hoaster]

Oh that's nice! Great pics.

 

[vlangel]

Oh that's nice! Great pics.

Thanks Michael!

This morning I made a decision about the fuge and Plank, the carpenter wrasse. I decided to move Plank into the 20 gallon long sump instead of the refugium. That way pods can still propagate with out being preyed upon. Of course pods and shrimp larvae that go from the fuge into the sump will be fair game. Still, I am sure that some will get through the sump and into the display before Plank finds them, especially at night when they are most active.

I had to take out most of the rock and red macro algae to net Plank. So when I put things back together, I arranged that most of the rock would be in the mid and back right. This leaves more lighted area for the seagrass to grow and the red macro algae is in more low light areas. It also just worked out that the hose from the display drain is greatly concealed too which is a plus.

Plank has a few smaller chunks of live rock and 2 large conch shells to hide in, which should make him feel more secure.

I feel good about these changes.

 

[vlangel]

So this is what the refugium looks like now. It is my hope that the entire front of the tank will fill in with lush shoal seagrass, while predominantly red macro algae will dominate the right back. I am also hoping that codium will be able to compete and grow somewhere, ha ha!

 

[Michael Hoaster]

Those changes make sense to me. Good thinking! You're optimizing the fuge too.

The fuge pic looks good. It's coming along nicely!

 

[vlangel]

Those changes make sense to me. Good thinking! You're optimizing the fuge too.

The fuge pic looks good. It's coming along nicely!

Thanks Michael. When your seagrass gets algae/cyano on it, is it mostly the tops of the blades? I am not sure of how to remove manually except I gently grasp the blades with 2 fingers and attempt to slide the algae off by pulling it upward. I have even considered trimming the tops of the blades and wondered if that would be better.

 

[Michael Hoaster]

The cyano I have now started on the sand, and climbed up. Back in the early days of the seagrass, it did get more algae towards the top, as you describe. And YES you can just prune the blade if you can't get it all otherwise. I wouldn't prune all blades of one plant. You want it to be able to photosynthesize to fuel growth. It sounds like you'll only need to prune off some tops, which should be fine.

 

[vlangel]

The cyano I have now started on the sand, and climbed up. Back in the early days of the seagrass, it did get more algae towards the top, as you describe. And YES you can just prune the blade if you can't get it all otherwise. I wouldn't prune all blades of one plant. You want it to be able to photosynthesize to fuel growth. It sounds like you'll only need to prune off some tops, which should be fine.

Ok, good to know. I won't go crazy with snipping the tops and actually wait till that is a last resort. Thanks for the info!

 

[vlangel]

Since I drastically pruned/pulled out the caulerpa and have begun to feed even heavier, I have observed that the cyano is receding. I have read that cyano and dinos are opportunistic when nutrients are too low, but found it hard to believe that the caulerpa could take up all the nutrients by themselves. They can nearly strip a tank of nutrients if allowed to grow unchecked. Again it comes down to maintaining a proper balance.

I like the green color caulerpa contributes to a tank but I need to find other sources to add green to my tanks. The codium I have is pretty but is a very slow grower.

 

[Michael Hoaster]

My favorite non-caulerpa green macro is Ulva. Grows fast, looks cool, can grow in a wide variety of lighting, and herbivores love it. And when the time comes, it's easily removed.