Cold tidepool/beachcombing aquarium

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Spotted a new nudibranch emerging from a holdfast today. Not a species that I have seen before. I think it might be Dendronotus dalli.

nudibranch2-4.jpg


nudibranch2.jpg


It had good timing, because I spent the afternoon plumbing in an accessory 10 gallon tank to use as a nudibranch habitat. I have a few too many of the murderous little critters roaming the main tank now for comfort.
 
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It has been a couple of really good days at the beach. It seems that the storms have to push from the north for much to wash up here and those are relatively rare. I filled my bag with holdfasts and picked up a bunch of other things as well.

Unfortunately, I woke up this morning to discover that the tank that I drilled and plumbed in yesterday cracked overnight. That's a real bummer. It is only a 10 gallon and barely leaking though, so it will probably hold out until I can replace it. I'm not looking forward to drilling another tank.

I got another anemone! I'm pretty sure that it is another A. artemisia. I have learned to carefully look at every rock with boring clam holes, because sometimes they have hitchhikers that survive the surf. This one is only about 1/3 inch.

anemone.jpg


And I picked up these unusual gooseneck barnacles with red lips:
red_gn_barnacles.jpg


Better pictures will have to come later, as the tank is pretty cloudy from dumping so many holdfasts into it.
 
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I picked up a piece of rockweed with a bunch of eggs on it, figuring it was a long shot at best, but there are fish in those eggs. They move around in the eggs when I shine the light on them. Probably sculpin eggs, I'd guess. It will be amazing if any of them manage to hatch.

eggs.jpg
 

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Looks great. I’d be surprised if you weren’t able to net some kind of small fish either living in the sand or otherwise a bait fish. But, I suspect what you might get would be a juvenile that would grow too big for your tank. You could try putting in a fish trap at night when the water is calm and checking after a couple hours.

That’s if you want a fish.
 
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It is more of a challenge than you might imagine. This is an exposed, shallow, purely sand beach and there is almost never calm water. The surf zone extends out more than 100 yards. On rare occasions at really low tides, I will find a few sandy pools and might be able to find some kind of bottom fish. I'm actually more interested in the inverts, so I could take or leave fish, but I expect that I will end up with some in surprising ways. I just added a bunch of eggs and perhaps some will hatch and survive. It is kind of fun sticking to only what I can find on this beach. It is like playing a game in hard mode. I could drive an hour and find rocky beaches full of life, but now that feels like cheating.
 
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This morning, I picked through the dregs of what washed up the past two days and came up with a third (and possibly fourth) species of anemone. These are still recovering from a couple days out of water, so I'm not sure what they are yet. I think they are probably either Epiactis or Urticina species, or possibly a mix of the two. There are about ten there and the largest, orange one is about 1/2 inch diameter. It is nice to have some more colorful anemones.

anemones-holdfast.jpg


And here is Hermissenda crassicornis hunting the choicest bits on a new holdfast. I had no idea how common these guys are. I have been getting one in every three or four holdfasts and I now have almost 20 living in their own habitat. Most are less than 1/4 inch long and you would never see them on the beach.

hcrassicornis_15.jpg
 
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Well, the new anemones have recovered enough to make an ID: Epiactis prolifera. The lines on the oral disc reach from the mouth to the outer edge, which is distinguishing. E. prolifera is a brooding anemone, which first shelters eggs within its body cavity. They are later move out and attached around the base of the parent. There are two color forms here: one with a red and white striped column and the other with an orange column. I think there are two parents with clustering progeny here - one on the right and one on the left. Interestingly, one source says that this species cannot tolerate exposure to air and sunlight, but these were at the top of the beach and had been out of the water for at least two days. They seem to have come through in reasonably good condition. They are said to be unusually active for anemones and I hope that they will spread themselves around the tank.

eprolifera3.jpg
 
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When those eggs hatch, Live Phyto, Rotifers and ground TDO (later). Best to set up a separate tank, 10G doesn’t have to be fancy, foam filter, water changes. But you have to many predators in your main tank for the fry to survive. Last year I raised Grunion from eggs, split in three batches. Tank, Sump, separate tank. The only ones that survived were the separate tank fry.
IMG_2481.jpeg
 
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When those eggs hatch, Live Phyto, Rotifers and ground TDO (later). Best to set up a separate tank, 10G doesn’t have to be fancy, foam filter, water changes. But you have to many predators in your main tank for the fry to survive.
I took your advice and moved them into a 10 gallon with nothing but macroalgae in it. I don't have rotifers, but I do have a plankton net and I ought to be able to provide them with more than enough plankton since I go to the beach every day anyway. I don't have any experience but I can see fully formed fish in some of those eggs, so I don't think I have much time to wait for mail order stuff.

My phone camera is really not up to this task, but you can see their little eyes reflecting:
fisheggs.jpg
 
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Today was anemone relocation day, since I had all these new anemones on different bits of holdfasts that I don't want to keep. It went OK, but was a lot more fiddly than I expected. I just could not get one to stick right side up, so it will have to figure things out on its own. Some of the little anemones that were attached to the parents have already moved out.
anemone-relocation.jpg
 

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Thanks for sharing! What a nice looking tank. No place like home :)

I myself have two Puget Sound biotopes. (60 gallon and 40 gallon) I’m curious what flow rates you’re using for your chiller. I’ve been experimenting with trying to maximize efficiency at 53 degrees F.
 
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I myself have two Puget Sound biotopes. (60 gallon and 40 gallon) I’m curious what flow rates you’re using for your chiller. I’ve been experimenting with trying to maximize efficiency at 53 degrees F.
I am just using a cheap 400GPH Chinese pump right now. It seems to do the job. It is running through a 1/10 HP JBJ Arctica. I was keeping the temp at 50, but I have increased it to 52 because I have fewer days with condensation that way. The tank is in an enclosed porch, where the temperature rarely rises above 60, so it doesn't have to do a lot of work. Back and sides are insulated with foam board.
 

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I am envious. This build is awesome, and I love the diversity of livestock in your tank. Following for future updates :)
 

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I myself have two Puget Sound biotopes. (60 gallon and 40 gallon) I’m curious what flow rates you’re using for your chiller. I’ve been experimenting with trying to maximize efficiency at 53 degrees F.
I am just using a cheap 400GPH Chinese pump right now. It seems to do the job. It is running through a 1/10 HP JBJ Arctica. I was keeping the temp at 50, but I have increased it to 52 because I have fewer days with condensation that way. The tank is in an enclosed porch, where the temperature rarely rises above 60, so it doesn't have to do a lot of work. Back and sides are insulated with foam board.
Roger that, I’m always eager for everyone’s input on cold marine aquaria. Would love to hear about your maintenance routine. I’d imagine it’s very simple with the water in your back yard (this is the excuse I used to get started myself).

I’m currently in process for finding a nitrate export method beyond water changes. Are you tracking water parameters, and if so do you have any methods or targets for stability?
 
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Roger that, I’m always eager for everyone’s input on cold marine aquaria. Would love to hear about your maintenance routine. I’d imagine it’s very simple with the water in your back yard (this is the excuse I used to get started myself).

I’m currently in process for finding a nitrate export method beyond water changes. Are you tracking water parameters, and if so do you have any methods or targets for stability?
I've never been big on water testing. I have done it a few times since starting just to get a sense for whether I have a bacterial community yet and it looks like I do. Ammonia was kind of high - running between 0.5 and 1ppm, but I feed heavily with phyto on a doser and it never increased beyond that range. I put in holdfasts partly covered in dead things and it never increased. Everything has looked happy and healthy except for gooseneck barnacles and sand dollars. I won't try those again until the tank is well established. I suspect that they might be finicky about clean water. This aquarium has a massive six inch deep sand bed of actual beach sand and a big pile of rocks taken from the beach, so I suspect that I have the bacterial community that it needs, even if it is not perfectly balanced yet. I figure that the macroalgae and the eelgrass will soak up a lot of ammonia and phosphates too.

I have skipped over the past 25 years of developments in the hobby and back in the day I didn't have a lot of money to spend on test kits, so I mostly just observed the tank and did water changes if things looked like they were going the wrong way. That is what I am doing for now while I catch up on aquarium science. Every other week, I go get about 15 gallons of water at the beach and do a water change. Whether it needs it or not, I am adding more plankton to the tank and I figure all my suspension feeders probably benefit from having more than just bottled phyto for their diet.

The tank has been going through an ugly phase with hair algae for the past month, but that seems to be reducing now. I have done very little other than scrape the glass and blow it off the rocks with a turkey baster. It has choked back my eelgrass, but I have a feeling that it will recover since it grows from rhizomes below the sand. If not, I will just get more when the next storm sends some.
 

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Roger that, I’m always eager for everyone’s input on cold marine aquaria. Would love to hear about your maintenance routine. I’d imagine it’s very simple with the water in your back yard (this is the excuse I used to get started myself).

I’m currently in process for finding a nitrate export method beyond water changes. Are you tracking water parameters, and if so do you have any methods or targets for stability?
I've never been big on water testing. I have done it a few times since starting just to get a sense for whether I have a bacterial community yet and it looks like I do. Ammonia was kind of high - running between 0.5 and 1ppm, but I feed heavily with phyto on a doser and it never increased beyond that range. I put in holdfasts partly covered in dead things and it never increased. Everything has looked happy and healthy except for gooseneck barnacles and sand dollars. I won't try those again until the tank is well established. I suspect that they might be finicky about clean water. This aquarium has a massive six inch deep sand bed of actual beach sand and a big pile of rocks taken from the beach, so I suspect that I have the bacterial community that it needs, even if it is not perfectly balanced yet. I figure that the macroalgae and the eelgrass will soak up a lot of ammonia and phosphates too.

I have skipped over the past 25 years of developments in the hobby and back in the day I didn't have a lot of money to spend on test kits, so I mostly just observed the tank and did water changes if things looked like they were going the wrong way. That is what I am doing for now while I catch up on aquarium science. Every other week, I go get about 15 gallons of water at the beach and do a water change. Whether it needs it or not, I am adding more plankton to the tank and I figure all my suspension feeders probably benefit from having more than just bottled phyto for their diet.

The tank has been going through an ugly phase with hair algae for the past month, but that seems to be reducing now. I have done very little other than scrape the glass and blow it off the rocks with a turkey baster. It has choked back my eelgrass, but I have a feeling that it will recover since it grows from rhizomes below the sand. If not, I will just get more when the next storm sends some.
I hear you there, I’m starting to have rising nutrients despite large volume water changes about 1.5 years into it. I’ll be curious if you encounter something similar in the future. Thanks for the response. Will be following your tank!
 

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That's awesome! Probably one of the coolest tanks I've seen in awhile too be honest. Got me wanting to do a tank like that.
 
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The new hermit crab finally made an appearance. He has been hiding in the eelgrass for days and barely moved, but he has run the full circuit of the tank today. Here he is investigating some new holdfasts. Pretty sure it is a Bering hermit crab (Pagurus beringensis). Hopefully, he will play nicely with the other inhabitants. So far, he mostly appears interested in sifting detritus.
hermit6.jpg
 
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My wife found this neat clay slab with Anthopleura artemisia anemones this morning. I never thought I would have to say this so soon, but I am going to have to start being choosier about anemones.

aartemisia-slab.jpg
 
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