Oyster Reef Ecosystem Tank

[Chasmodes]

After a more research, I think that the anemones in the fish tank are actually a different species, the Starlet Anemone - Nematostella vectensis. This would explain why they prefer the sand bed to the shells. They're a type of burrowing anemone. There is another species of burrowing anemone, Edwardsia elegans, also whitish or clear. But, after looking at photos of each, I'm convinced it's the starlet anemone. "This anemone is now a widely used experimental animal for studies of genetics and developmental biology, because of its hardiness and simplicity." --National Exotic Marine and Estuarine Species Information System

[Chasmodes]

There's a study of the venom of these anemones, and the effect on grass shrimp, killifish larva and killifish adults. When observing grass shrimp touching an adult polyp, the grass shrimp darted away, suggesting that the anemone's sting was a good defense.

Anemone adult polyps, when in contact with killifish larva, captured and ate the larvae.

Adult killifish will eat the adult anemone polyps.

So, the sting of these anemones shouldn't bother adult fish in my tank, but, as I suspected, will eat fish larvae.

Edit:
The study was, "Dynamics of venom composition across a complex life cycle" by Yaara Y Columbus-Shenkar, Maria Y Sachkova, Jason Macrander, Arie Fridrich, Vengamanaidu Modepalli, Adam M Reitzel, Kartik Sunagar, Yehu Moran

[Michael Hoaster]

Good research. I love me some scientific study articles! You can learn so much from them. And because they are from outside the hobby, they aren't 'infected' by aquarists' perspectives. Not that that's a bad thing, I just like the 'pure' stuff, that I can add my own perspective to.

[Chasmodes]

Thank you Michael. I try to find out as much as I can about my critters, and scientific publications are sometimes the only reference you can find.

This was an exciting weekend in some ways. I went with some friends on a collecting trip. On the down side, record rainfall over the past 16 months reduced the salinity in the Chesapeake bay dramatically, so much so, that it's almost fresh water. Blue catfish are regularly caught throughout most of the Maryland section of the Bay. In the past, their range was about the most upstream Northern section of the Bay.

As you might suspect, our collecting results were tough. We managed only 9 benthic fish (2 tiny skilletfish, one huge female striped blenny stuffed with eggs, and a handful of naked gobies). We also caught one pipefish, a few small american eels, some grass shrimp, a bunch of juvenile mummichogs, silversides, mud crabs, a half dozen fourspine sticklebacks, and grass shrimp. Of what we kept, most of it went to our local public aquarium.

I kept a pair of sticklebacks for my 20g high (second video), a few oyster shells with live mussels, and 5 mud crabs. I also collected some Ulva and floating widgeon grass. Within the widgeon grass looked like strands of Elodea. I also collected another species of macroalgae that I have yet to identify (in the first video). Widgeon grass, some Ulva and Elodea, grass shrimp, amphipods, and the sticklebacks went into the 20g high (second video). Some Ulva and Elodea went into my 20g long fish tank, along with a couple oyster shells with mussels on them, and the mud crabs.

My friend that I went with also has an oyster reef tank, and gave me a small hermit crab and an oyster shell with barnacles on it. I'm not sure if the oyster is alive or not.

This video is my 20g long, my fish tank, showing the new additions.
https://www.youtube.com/watch?v=qPijclay-boaikj8&t=16s

This is the 20g high, featuring a ghost anemone and the sticklebacks.
https://www.youtube.com/watch?v=QT4Jqrl3xag

Enjoy!

[Michael Hoaster]

Collecting sounds awesome, and sometimes, hit or miss. That's so cool you donate stuff to your local aquarium. Good luck with your new flora and fauna!

Clicking on your vid links yields a "Video Unavailable " message.

[Chasmodes]

Thanks Michael.

Sorry about that. I forgot to make them public. Fixed now.

[Chasmodes]

Last night, I took another video of the fish tank, because the one that I posted yesterday was filmed when the water was still cloudy, and there were some really blurry scenes. The water in this video is much clearer, probably because the live oyster has been doing some filtering! Also, notice how fat the female striped blenny is. She is full of eggs. She has been laying eggs a couple times each week and is ready again.

https://www.youtube.com/watch?v=mAX4H5PnVhM

And, that is the subject of the second video, the live oyster in my tank. When my friend gave it to me, I didn't realize it was alive until after I put it into the tank. It has a lot of small to tiny barnacles on it too, along with some other life. I was watching it with my magnifying glass, and decided that it was cool enough to deserve it's own video. Plus, a mud crab photo-bombed the whole thing.

https://www.youtube.com/watch?v=3xsRo7kDFy0

[Michael Hoaster]

I like the color injection from the plants. You've got a fun community of fish there. I'm sure they give you hours of entertainment! The Oyster with the attached Barnacle is cool. What do you feed them, phytoplankton?

[Chasmodes]

Thanks Michael. I need to get another view of that oyster. It's loaded with little barnacles and I think, tiny tube worms.

I feed my filter feeders Oyster Feast every other day. I may need to change to every day. I want to start my own phyto cultures to save money and then I can feed them daily. Oysters need a lot of food, as do the mussels.

I'm going to build my sand bed after your design. My friend has some eel grass that he'll give me. After seeing it in his tank, it looks great and I want some. I think that using your methods, with the new lighting, I should be able to keep most plants alive. I need to get it in gear and get it done.

[Michael Hoaster]

You probably know this already, but Florida Aqua Farms sells phyto culture kits at: http://florida-aqua-farms.com/

That's exciting your going to get eel grass. Woo! I'll be following!

[Chasmodes]

I wasn't very optimistic about the eel grass, because I haven't been able to find any at my collecting spots. My friend has a good source that can get it, plus, he has a bunch now and said he'd give me some. So, I'm a bit fired up about it. I would like to get a bunch of stuff done this weekend, that's the goal, anyway. Now that it's a realistic possibility to get some, I'm very motivated!

Thanks for the info on the phyto culture kits. I wouldn't rule out ordering from them. But, the plan now is to make a DIY set up. My friend who has the eel grass also has a phyto culture going and will set me up for that too. It's good to have friends in the hobby that are interested in the same stuff (he has an oyster reef too).

[Michael Hoaster]

I'm fired up too! Exciting time for you. That is awesome you have a friend doing the same things. You'll be able to help each other out so much.

If you really get after it this weekend, make sure to keep us apprised!

[Chasmodes]

Looking back at Michael's thread, I was trying to refresh my memory of what exactly he did...from the thread:

Originally Posted by Michael Hoaster

...I got it from Florida Pets. It is actual, black, stinky mud. So you don't need a lot.

Rather than planting in clean sand, I want to give the grasses a fertile home right from the start, rather than waiting for nutrients to build up. And since they are true, rooted plants, they take up a lot of nutrients from the soil.

So hopefully, my dirty sand bed will provide a good home to both the grasses and micro fauna, adding nutrients and diversity to the foundation of the ecosystem.

While we're on the subject, I wanted to elaborate on the reasoning for using multiple sand grain sizes. Layers of different grain sizes are conducive to different pore water oxygen levels and thus different kinds of bacteria. By layering with coarse at the top, medium in the middle and fine on the bottom, I should get a gradient from aerobic to anaerobic to anoxic conditions. This should foster diversity in bacteria, which is a good thing. Also, the coarse top layer provides habitat (and refuge) for pods and other tiny creatures to feed on accumulating detritus.

Now, my check list:

1) Black stinky mud - check. We have plenty of that in the Bay. It should have plenty of critters in it too.
2) Live sand - check. I will have to keep this tank fallow of fish for a time period, because I'll be collecting my own sand.
3) Different grain sizes of sand - Since I'm collecting my own, my version of this will be regular sand mixed with small shell fragments, which are abundant in the Bay. There will be plenty of life in it too. I'll be sure to add some shark teeth in my sand bed to in honor of the great number of miocene fossils found along the Bay's shorelines. This should provide cover for pods and other critters. I'll also use regular play sand from HD, which is probably a different grain size. That sand will be washed, since it's store bought.

Since this tank will have a good amount of flow, I'm hoping that it will stay in place. If you can imagine by looking at the oysterscape video below, I'm thinking that the grass will grow in the cavern. My flow will be generated by a Maxspect Gyre. Will I be able to keep the sand and mud in place? I have no idea. I guess I will have to test it out before attempting to plant anything.
https://www.youtube.com/watch?v=I0d8HfyIGMg

[Michael Hoaster]

That all sounds good to me. I'd recommend putting and inch or two of sand on top of the mud, to help avoid cloudiness. When I reworked my sand bed to slope like a sand bar, my dirt layer got 'randomized'. That gyre pump is likely to move sand around in an 18 inch deep tank. To prevent that from happening you could put a layer of very course crushed coral gravel on top. In addition to not getting blown around, it provides great refuge space for pods, etcetera. Basically, put the finest sand/mud at the bottom and the coarsest stuff on top. I added a bag of play sand as well. It is a silica sand, so it should help fuel diatoms, sponges and snails growth. Most aquarists try to avoid diatoms, but they are the foundation of all life that will come after it.

I have no experience with Eelgrass, but I'm sure their's some info on them out there somewhere. How deep of a sand bed do you have planned?

I'm psyched for you!

[Chasmodes]

Thank you Michael for the suggestions! They make total sense. I was hoping for a 2-3" sand bed.

Yesterday, I made a bunch of progress on my build. How? By almost finishing the roots. I applied the grout to the roots and I'm pleased with how they turned out. I may need another coat of grout...I'll know more once it finishes curing. Next weekend, if it's ready, I'll paint the roots with Drylok/cement dye to seal them in for good. This will prevent the pH problems that grout or cement create by sealing everything in. After that, the roots will go into the 75g tank, freeing up my workbench to become my tank stand for the big tank.

I hope to have the 75g stream tank up and running very soon. Next steps after the root is done are to collect gravel, sand and rocks, then cycle the tank, then collect fish! Yay! This was a huge burden off my mind. It's been bothering me for a long time. I'm ready to roll now.

Here's a video of the 75g stream tank build so far: My US native fish stream tank build is back on track. Yesterday, I made a good bit of progress on the DIY root construction by adding brown grout to the root structure. The next steps toward setting up the tank are to paint the roots with Drylok mixed with cement dye, collect rocks/gravel/sand for the substrate, fill up the tank with water and cycle the tank, construct a top for the tank, purchase lighting capable of growing grasses and plants, and collecting fish. This tank should be up and running in a few weeks! Here's a video update of the build so far:
https://www.youtube.com/watch?v=Cb-OR9ZatNE&t=6s

[Chasmodes]

I took a few pics of the latest version of the roots in the tank, to get a sense of what the roots and rock wall will look like. Sorry that the pics look a bit blurry.




This view from the left side of the tank shows the functionality of the root design. The big hole underneath is where my powerhead will be, mostly hidden from view by the root structure from the front of the tank. That was my goal with the roots, to hide equipment. Another thing that I'll do is paint the side and back of the tank with Drylok/black cement dye, to hide the silicone adhesive and equipment from view.

[Michael Hoaster]

The stream tank looks great! I look forward to seeing how it ends up. Your fake roots turned out fantastic. You've made great progress!

[Chasmodes]

Thank you Michael. I can see the light at the end of the tunnel!

[Chasmodes]

Yesterday afternoon, I had some time to work on the roots. However, when I went downstairs, I remembered that my paintbrushes were all ruined. Also, I opened up my can of Drylok and it was solid as a rock. When I first bought the can a couple years ago, it fell out of my truck, opened up, and spilled white Drylok on my driveway. Apparently, when I put the lid back on, I didn't put it on tight enough, and air got in there. I was also out of the charcoal color cement dye, which is necessary to bring out the deeper nooks and crannies of the work. So, I went to HD and they had everything that I needed in stock.

When I got home, I slapped on the first coat a Drylok, pretty thick too, to make sure that all of the root surface was covered, to seal everything in. Drylok tends to shrink when it dries, I think, because sometimes, small holes in your work tend to open up when it dries and they require a touch up. I only found two of those last night, so I'm really happy about how this coat went on. The roots look pretty good now, as the pink foam is finally covered, but, they aren't the rootsy color that I want. I will add a few new coats of Drylok to add color and try and bring out some realism. I may add a few tricks to do that too, regarding texture. I need to think about how to do that, and if I can pull it off, I'll review the how afterward.

Here is the Drylok that I used. I prefer the Gray. It's important not to get the "extreme" Drylok product because it has mold inhibitors and other chemicals that could be harmful to the tank. This is latex based Drylok. I mixed it with Quikrete charcoal color cement dye. It's easy, just pull out some paint, pour in the liquid dye, and stir it in.


I painted the first coat on thick because I really want to seal everything in to prevent pH issues from happening.


First coat finished, from the front left side.


A close up of the split bark section. It looks much nicer with the pink foam board finally covered up. I'm really happy with how this turned out. Drylok is great because if you have detail carved into your work, it does not fill in the gaps and cover it up. This is the only exposed foam after the grout coating.


Showing the knot and hole. I think it turned out too big, but I can live with it.


More of a left side view.


It's getting there...I can't wait to get home from work and work on it again tonight.

[Michael Hoaster]

That looks amazing!

[Chasmodes]

Thank you Michael! Almost there!

[Chasmodes]

I made a short video to introduce everyone to the crabs that are currently in my tank. Enjoy!

https://www.youtube.com/watch?v=H8Fdcr6Pwuc&t=5s

By the way, the blennies killed one of my crabs. After filming this, I found a dead one, upside down, with the belly eaten out. I've seen them attack the crabs before. This one was picked on the most, because the last time I saw an attack, a male blenny lopped off the victim crab's claw. It's interesting, because they leave the hermit crab alone!

[Michael Hoaster]

Cool crabs vid! How big are they now, and how big can they get? Will your clean up crew by crab-based in the big tank?

[Chasmodes]

Thank you Michael. The Harris mud crab only gets to be about an inch and a half in diameter (carapace). The black-fingered mud crab gets a little bigger to about 2" wide. The hermit crabs may get a little larger than the one that I have, but not much.

The crabs will definitely be part of the CUC. Now that I've seen how the fish and other crabs react to the hermit crabs, I want more of them. Why? The mud crabs are fine, but, they hide a lot and don't roam around, so their clean up duties aren't that effective. The hermit crab is all over the place. I want snails, but, I haven't found them at my collection sites (probably not looking in the right places, and, they weren't really on my radar). Keeping them long term depends on how the fish react to them. Will they ignore them? Or, will they kill them? I have a ton of different worms and lots of little anemones and jellyfish polyps, so, they help with the clean up too.

[Chasmodes]

Sad news...After work on Thursday, I found my largest skilletfish, the one that was guarding eggs in some of my videos, dead. It stopped eating for a couple weeks, but the last month has been eating heartly and was back to normal. I have no idea what happened. I'm down to one skilletfish now.

The rest of the fish are doing great.