Posts Tagged ‘toxic’

The Post – Scarlett O’Hara “Labor and Delivery” Watch, and Ammonia Monitoring

March 27, 2008

For the last several days, Scarlett has been sitting on top of, or in, the water filter. Even though I shut down the filter Tuesday (so no babies would get sucked up in the filter material should they hatch), she continues to stay inside the empty filter. I guess it’s like a cave – nice and sheltered. She hasn’t come out to eat, but then I imagine that filter material has a ton of bacterial and algal critters all over it.

She DOES need to be in water at some point and on that count I’m not sure how long she can stay out of the water and in the filter. I tried chasing her out of the filter Tuesday afternoon, partially to see if she was okay, and partially to see if overcoming inertia and forcing her out would keep her out, but within minutes she was back inside of the filter. Who knows if she climbs out at night when the lights are off, to go for a swim.

Wed morning she was inside the filter, still sitting at the bottom. She wasn’t moving so I jiggled the filter cartridge enough to see her move. I left her alone until Wed afternooon when I pulled the filter cartridge up a bit. Scarlett O’Hara rushed up and out of the water filter and down into the water. She sat underneath the water filter, so I guess she’s just “staying put in sheltered places.” However, she does appear to be okay.

I tried giving her a couple of shrimp pellets, assuming she must be hungry, but she basically pushed them aside. She did pick at the calcium sand, so I expect she’s looking for algae. I dropped in a couple bits of algae pellets but she ignored those too. So either she isn’t hungry due to the pregnancy, something’s wrong, or she’s full from eating whatever is on that filter packing material. Right now she is still out in the tank and has even wandered over to the air bubbler at the other end of the tank. I am heartened to see her doing her usual activities: climbing up on the bubbler, trying to climb up the side of the tank, and resting on the suction cups behind the air filter that hold it in place. So, for now, I guess, all is well.

My only “curiosity” is “will she stay out into the water to deliver the babies?” I expect she will given that female fiddler crabs look for places in their estuary homes that have active water currents so the eggs can be washed out to sea. So “instinct” alone should propel her back into the tank water at about the time of delivery, no matter how much she likes it inside the water filter. Given she did it right the first time, I can’t imagine she’s forgotten what she needs to do. I missed the delivery the first time so I don’t know exactly what she does to release them. I hope I catch it this time. Also, I do wish I could just ask her why she likes living at the bottom of a dark empty water filter. In lieu of that conversation, all I can do is watch and wait…..

Water parameters Wed afternoon were good: Nitrates 10, Nitrite 0, Hardness >300, Chlorine 0, Alkalinity 300, pH 8.0 and the Ammonia monitor is in the “safe” range at < 0.02 ppm.

The ammonia monitor is a Seachem Ammonia monitor that you can hang inside the tank. No test strips or kits. This one is called the Seachem AmmoniaAlert for Fresh and Marine tanks. It continuously monitors the free ammonia level in the water for over a year.

The monitor is color coded for concentrations:

– Safe (<0.02 ppm), Yellow

– Alert ( 0.05 ppm), Green

– Alarm ( 0.20 mg/dl), Sky Blue

– Toxic ( 0.50 mg/dl), Lavender

The insert says that the “Alert Level” of free ammonia can be tolerated for several days; “Alarm” for a few days; and “Toxic” is rapidly harmful. It would have been interesting to see what it read when I had the phytoplankton overgrowth and high nitrites, the first time I did this.

While I knew that monitoring ammonia was important and somehow related to the level of nitrites and nitrates, I wasn’t sure exactly what was going on. I found a good website, The Tropical Tank, done in the UK, that discusses water chemistry, and in particular, ammonia, nitrites, and nitrates. It’s called: More on the Nitrogen Cycle: Ammonia, Nitrite, and Nitrate

In short, there should be no ammonia or nitrite in a mature tank. Any ammonia is present in two forms: ammonia (NH3) and ammonium ion (NH4+). Ammonia is more toxic than the ion, and the higher the aquarium pH, the higher the ammonia level. Since brackish and marine tanks are basic, ie higher pH, ammonia toxicity is a constant risk.

Ammonia in a mature tank is oxidized by nitrogen-fixing bacteria, to nitrites and again, in a mature tank, nitrites are oxidized to nitrates. While you don’t want to see nitrates run high, a lower level , say < 50 ppm, are considered okay, 25 ppm is even better. If your tank isn’t cycling well, is new and not enough nitrogen-fixing bacteria, you have too many tank inhabitants, or you’ve overfed them, ammonia (and hence nitrites and nitrates) will start to spike.

The bottom line, the appearance of rising ammonia levels is the first clue that things in the tank are not well and even toxic. Given that my last endeavor with crab larvae resulted in mass death due to high nitrites (and yes, the phytoplankton caused an algae bloom that caused ammonia and nitrites to spike and I won’t use it again) I thought it might be interesting to monitor the ammonia levels in the tank on a continuous basis through this project.

This article also gives information on how to start up the nitrogen cycle in a fishless tank. I wondered how you get the cycle going when there are no fish or fish wastes to start the process.

If you are interested, this same UK website has two other interesting articles:

The Basis of Cycling: a good overview of the maturing nitrogen cycle in aquariums

Fishless Cycling Data provided to them by a US forum member, William Wallace; some concrete data on how Mr. Wallace actually did this process.

To return to the tank and Scarlett:

Wed evening, the water looked cloudy and while other parameters were still fine, I noticed a trace amount of nitrites now. I also noticed a few green spots in the yellow safe zone of the ammonia monitor. The green spots are the beginning of a change to “alert.” Given that I think we’re a few days away from birth yet, I decided to turn the water filter back on for a day or so to try and improve the tank conditions. I suspect that adding Scarlett to the tank was enough to catalyze the nitrogen cycle into high gear. It’s to be expected to see “some” ammonia and nitrites, and there also is a “good” level of nitrates, but still, I don’t want to lose the battle of water quality before the babies are even born. I will continue to monitor water quality closely today today. If necessary, I’ll do some water changes, but I would rather not do that. Since the nitrogen cycle is in its early stages, every time I take water out and put in new water, it removes some of the very nitrogen-fixing bacteria I need. The gentleman at the aquarium store said it would be best to just let the tank evolve. So as long as we don’t go beyond “alert” on the ammonia monitor, I’ll let it “evolve.” Otherwise…I’ll have to start water changes. I wish I’d known earlier about the fishless cycling Mr. Wallace did. I could have done that with this tank to get the nitrogen cycle established before moving Scarlett into it.

Tank parameters this morning are the same as yesterday afternoon and Scarlett is out walking around the tank, so, no better, no worse.

Stay tuned.

The Post – The Fiddler Babies are Dead, But We’ll Start Over And Prove Horseyhannah Wrong!!

March 10, 2008

The fiddler babies are dead.

I am sad, because I really did like the fiddler babies. I looked around on the web last night for clues to their demise and that’s when I got ticked.

The Discovery Channel’s Animal Planet Online Forum had a discussion of how to raise fiddler crab larvae. “Horseyhannah,” a senior member on the forum basically told a member who asked how to raise fiddler larvae that it’s so hard and requires hundreds of thousands of dollars of equipment to simulate ocean environments, waves, tides, etc. so it’s really not possible. Horseyhannah told the person to just enjoy the adult fiddler crabs and don’t bother to raise the babies. Needless to say, the person asking the question was polite, said thank you, agreed it will probably be hard, but would still like to know horseyhannah’s info source…just in case she decided to raise them anyway. My answer to that person is: GO FOR IT!!!! PROVE HORSEYHANNAH WRONG!!!!!

In fact, I am determined to do just that. In my book, Horseyhannah has thrown down the gauntlet and I am determined to prove her wrong.

I will concede failure on this first attempt. I am sad as I was so looking forward to having some fiddler grandchildren survive. I was frustrated and disappointed because contrary to the advice above, I think it was not only possible, but it was happening. Because I lost them so quickly, that tells me something overwhelming happened in the tank to kill them all off at once.

To review, by Friday afternoon, there were no babies moving around. It was a rapid decline, and up until that point, we still had quite a large number alive. I have to conclude it was a water quality issue and I think the biggest culprit was the live phytoplankton. But to go through this methodically, let me look at several things. If it were salinity, ie they didn’t like the marine environment I don’t think they would have lived that long in it to start with. I suspect the following things were problems:

1) I used gravel and we did lose MANY babies because they burrowed into the gravel crevices and died there.

2) The nitrite levels in the water spiked suddenly and got very toxic. Thoughts on this point:

a) I didn’t get the tank set up early enough to have a mature and well-functioning nitrogen cycle.

b) I either fed them the wrong food, or too much, or both. The wrong food or too much food meant it didn’t get eaten, sat in the tank and rotted. OR it created a huge algae bloom that raised nitrite levels beyond a tolerable level.

c) I didn’t change the water fast enough once I realized the nitrites were a problem, though given the phytoplankton issue, I was probablly fighting a losing battle from the beginning.

d) I no doubt lost babies doing the water changes because my only option was to bail water out of the tank and pour it down the drain

So boys and girls, what have I learned from this first attempt that can be done better next time?

1) I will use calcium sand not gravel. Aside from the fact that the babies won’t get trapped in the substrate material, the calcium sand will provide enough calcium for the babies to stay healthy during many molts.

2) Figure out the right food and amount. The gentleman from Finland whose article I quoted a few days back (he raised the Red Clayed Mangrove crabs) fed his larval crab Artemia…brine shrimp. He had a hatchery right in the tank to have a fresh supply. He also used something called JBL Nobilfluid for when the larvae were too small for the brine shrimp. This product is probably similar to the Small Fry liquid food I was using. It it made by a company in Germany and I’m trying to find out if it is marketed here. It has 50 different vitamins and minerals as well as brine shrimp and is geared for newly hatched aquatic animals too small to tackle live brine shrimp yet.

3) DON’T USE LIVE PHYTOPLANKTON this time. In spite of an almost 50% water change, I could not get the nitrite levels down. In fact, they kept rising. Now I am finding information that phytoplankton excrete nitrites. The better the phytoplankton did, the higher the nitrites. And with each feeding I basically inoculated the tank with more. I created my very own algae bloom which released such high nitrite levels, the babies were doomed.

Frankly, the tank seemed to be doing okay until I started using the phytoplankton. I would feed the liquid Small Fry food and while the tank would be cloudy initially, it cleared quickly, telling me the babies ate the food. At that point, in spite of it being a new tank with an unestablished nitrogen cycle, the nitrite levels stayed pretty low. However, once I started using the phytoplankton, the tank got cloudy quickly, the nitrite levels spiked, the water had a greenish tint, and the larval crabs numbers dropped dramatically. So, NO phytoplankton.

4) For water changes, instead of bailing water out, I will use the water bubbler as my “filter” to keep the babies in the tank, and let gravity siphon water out of the tube. I have the bubbler’s pump set up beneath the tank and have a regulator valve in the line to keep water from back-flowing from the air bubbler, into the pump. If I remove the valve and let the tube sit in a bucket, it will slowly siphon off water through the bubbler. This should let me slowly get water out for changes, without bailing larval crabs out of the tank and sending them down my kitchen drain.

So. I will start over. Admiral Byrd is doing his part, trying to get Scarlett O’Hara to notice him. Scarlett O’Hara has been eating and hanging around Admiral Byrd’s cave den. I figure it’s only a matter of time before Scarlett has eggs again. Therefore, tomorrow, I will take down the nursery tank, clean it out, get some calcium sand, and get that tank up and running again with the live rock in it, and get that nitrogen cycle stable.

We are going to try this again! My husband and I would love some fiddler grandchildren, 🙂 and even he said that we must prove Horseyhannah wrong!!! Stay tuned.

The Post – Scarlet O’Hara Lives! And How I Came to Love Fiddler Crabs

January 25, 2008

After almost 10 days without a sighting, FINALLY yesterday afternoon, I spotted Scarlet O’Hara. I wasn’t sure at first if she was just a corpse, dangling upside down inside the Live Rock with her eyestalk hanging down, but shining the flashlight into the rock’s cavity at 5 minute intervals, I was able to determine that a) she actually had moved her position, and b) on the second and third times, she reacted to the light beam and flinched. This latter point was important because it meant the movement was deliberate, not the result of her just being bobbed around in the cavity by the water’s movement.

Relieved to know she wasn’t dead, I went ahead and did the water change. (More on that below) Then last evening, Scarlett O’Hara emerged from the Live Rock Cavity, and slowly started moving around. She resembled a patient just released from the hospital – someone tentative in her steps and tired after her ordeal.

Okay. Right about now, I’m sure anyone reading this is wondering what the hell I am talking about. Let me back up to the beginning and give you the Readers’ Digest version of events. I am contemplating setting up a separate blog – Crab logs – to capture all the events since the beginning of this endeavor, for those purists who only want the “lab notebook stuff.”

As I’ve mentioned I am writing a mid-grade novel called Under the Pier. At least that’s the “working title.” The protagonist of the “under” the pier side is a hermit crab. While I had no trouble pinning down facts about the creatures in that world, those chapters lacked “heart.” They read more like a nature guide. My husband read the first few animal chapters and noted that frankly, he didn’t care about the creatures. That’s a death knell for any book, whether the characters are human or animal. The whole point of reading a story is to feel what the characters feel, live through the story struggle with them, and stay along for the ride because… you CARE about them. If my husband didn’t care about them at chapter 2, I had a problem. So, back to research.

It occurred to me that I just hadn’t captured what it felt like to be an undersea creature. Since I can’t live underwater, an aquarium is the next best thing. I couldn’t have a marine hermit crab like the one in my story as a pet because that meant setting up a salt water tank, something reputed to be very difficult. PetsMart had something called “freshwater crabs.” A freshwater aquarium meant cheap, at least cheaper than a saltwater one, and easier. I’d had aquariums as a kid. I figured I could set up a small tank very inexpensively, get a couple crabs, and voila….live research that would teach me how to emotionally bond with something I normally eat in garlic butter. As I’ll describe below, “cheap” didn’t take place, but emotional bonding did. My husband noted that I bought myself $4 worth of fiddler crabs, and $100 worth of support gear. 🙂 In reality, it’s been way more than that by now, but . . . more about that later.

Anyway, I bought two males, not through any particular strategy. Those 2 just happened to wander into the net the teenage employee swished through the store’s tank. I rushed home with my new “pets” and all my gear and rapidly set up the tank. Normally, when you set up an aquarium, they recommend getting everything established before bringing home your fish. However in this case, I figured why bother setting it up ahead of time when the saleslady made it sound like all these guys needed was some water and a bubbling air tube. Again, more later.

The larger male immediately ran around his new tank, explored every aspect, took command of the gravel hill (they need an area where they can be out in the air for up to 50% of the time), and showed no fear. Given his apparent “explorer” mentality, we named him after the South Pole explorer, Admiral Byrd. The smaller male immediately bolted under the water filter and stayed there for 2 or 3 days. Even when he came out, he skulked around in the background. My husband noted that he acted like the Peter Lorre character in the movie, the Maltese Falcon, so we named him Peter Lorre.

I’m going to skip over the travails of learning I should have set up the aquarium first before buying the crabs, the fact the people had us buy the wrong food (how are bottom-dwelling crabs supposed to eat krill shrimp that only float on the water’s surface and don’t sink?), and the many things that made me realize these crabs really do need more than a bubbling air tube if they were to live longer than the 2 weeks PetsMart’s written guarantee said they would.

As it turned out, Peter Lorre made it about 3 weeks before he died. I think his poor little body just wasn’t up to the stresses of toxic nitrite and nitrate levels, not to mention the fluctuating salinity levels (see below). By the time I learned about Live Rock and how it speeds up the nitrogen cycle in the tank and makes things healthy and non-toxic, Peter Lorre just stopped walking one day, tumbled off the live rock, and dropped headfirst to the bottom of the tank, dead. I was heartbroken…he was the quiet timid one, and I did like him. My husband couldn’t understand how I could care about him given that I ordinarily do not hesitate to go to a seafood restaurant and consume his cousins with great enthusiasm. Doing a twist on that line from the Godfather movie about things not being personal, but business, I said to my husband, “This is personal, not lunch.” When things get personal, you go to Google for answers.

Now, for any aquarium geeks – a couple things. Live Rock, as mentioned above, is rock taken from a tropical coral area, and contains microscopic sea life and bacteria. By adding a1 pound chunk of cured Live Rock (ie has been allowed to sit in a salt water tank and age and no longer smells like a salt marsh) to the tank, it essentially seeded the tank with nitrogen-fixing bacteria. They speed up the establishment of the Nitrogen cycle. That’s where toxic ammonia and nitrites generated by the biologic wastes in the water, are converted to nitrates. Eventually the levels of ammonia, nitrites and nitrates drop to zero. The Live Rock also has the benefit of leeching calcium into the water. This comes in handy for keeping things like pH and calcium at stable levels. Crabs need high calcium for molting. Anyway, once I added Live Rock to the tank, the toxic conditions subsided rapidly. But not in time for Peter Lorre.

I also learned that the crabs I bought were “red-jointed fiddler crabs,” otherwise known as Uca minax. Sometimes PetsMart sells the yellow-clawed ones, Uca pugnax, or mud fiddler crabs, but I definitely got the red ones. While these crabs can survive in freshwater, it apparently shortens their lifespan considerably. I read somewhere that they can live a year or more if kept at the right salinity. I figured salinity meant “marine.” After all, if they weren’t freshwater crabs, then they were salt water crabs. I went out and bought aquarium salt and made it up to the regular marine aquarium specifications, a minimum specific gravity of 1.020. I eagerly added the water to the tank figuring my guys would react with glee. Instead, Peter Lorre went into a daze and foamed bubbles out of his shell. Admiral Byrd bolted out of the water like I’d just added sulfuric acid and literally tried to climb the walls of the tank to get out. I didn’t understand it. I’d followed the directions and they “should” have liked the water, but obviously they didn’t. Even fiddler crabs deserve not to be in pain so I added some plain water to dilute things. They settled down.

In hunting around some more on Google, I discovered that these crabs are in reality, brackish water critters. That is that “estuary” type environment where the rivers meet the sea. The water is neither freshwater nor saltwater. Brackish water has a much lower level of salinity. Further, I found a study of fiddler crabs in the rivers of Delaware that really illuminated the problem. Uca minax – the red-jointed guys – prefers water with a specific gravity of around 1.008 – 1.018. Any higher than that and the LD50 (the time it takes for 50% of the population to die) is 2- 3 weeks. Same if you put them in freshwater.

Interestingly, according to the study, the yellow-clawed guys LIKE the higher salinity. If I’d had Uca pugnax crabs instead of Uca minax, they would have loved the higher salinity water. But my guys hated it. They needed….brackish. That’s how it goes with me. I start out to have a simple freshwater tank, then accept I must make it marine, only to find out I have to actually set up a brackish tank…something by the way, very few people do probably because there’s no books on the subject. In any event it’s been quite the adventure, and I sure have learned a lot, becoming a bit of an expert now on maintaining a good brackish water environment, a source of pride for me. However, this should explain now, my husband’s comment about $4 worth of fiddler crabs, and a $100 worth of support gear. It goes without saying I needed a gauge to monitor specific gravity not to mention water conditioner, solutions to decrease the ammonia until the Live Rock bacteria kicked in, and test strips to check the water…a lot. 🙂

Anyway, end of geek moment and back to the story:

Well, now that Peter Lorre was dead, Admiral Byrd was beside himself. He sat in his little cave tunnel near Peter Lorre’s dead body and just twitched. I thought he’d eat Peter Lorre given that they are scavengers, but apparently fiddler crabs don’t eat their friends. I removed Peter Lorre and gave him a proper pet burial in our front yard, next to the gerbils, hamsters, and pet rat buried out there. Then I set out to buy Admiral Byrd more friends.

I found this amazing aquarium store on the outside of Raleigh, NC – Fish Pros – Fishprosnc.com SALT WATER TANKS and ALL KINDS OF GEAR and PEOPLE WHO KNOW WHAT THEY’RE DOING!!!!. In fact some of their staff are marine science students or professors at NC State University nearby. In any event, I left there with not just ONE more friend for Admiral Byrd, but three. And this time, there would be WOMEN!

I figured keep the numbers even, so I bought 2 females and one more male. The man at the store noted that having the females would produce some neat “claw-waving” mating behavior in the males – the crab equivalent of “Hey baby, check me out!” Also, since females weren’t territorial, it was possible to have more crabs in the tank without having fights. Needless to say, Admiral Byrd perked right up when he saw he had friends, and when he realized there were ladies, well, he hasn’t stopped waving his claw since.

In any event, the male struck my husband as the “Rhett Butler” type, so, the new guy became Rhett Butler. That meant following the Gone With the Wind motif for the ladies names. The larger female demonstrated an overbearing, fearless, almost aggressive streak. She became Scarlett O’Hara. The more timid, fragile female, is Melanie Hamilton.

Again, for whatever reason, we lost one of the crabs – Rhett Butler lay dead in the back of the tank. No outward evidence of “foul play” ie – Admiral Byrd killing him off for territory or women. Again, another pet burial in the front yard. However, since then, the remaining three crabs have done fine. Yes, the women get fed up with Admiral Byrd chasing them around. And Yes, Melanie Hamilton got tired of Scarlett O’Hara stepping on her to get to the food pellets. Melanie Hamilton spends most of her time living INSIDE of the Live Rock chunk. She does peek out the front or side entrances long enough to grab a food pellet and pull it inside, and every now and then she will climb out and wander around, but she’s very skittish and races back in the rock at the slightest provocation.

My Scarlett O’Hara concern started about 10 days ago. She enlarged the front entrance to the Live Rock, ie, pulled out a bunch of gravel and tunneled under it to get inside it with Melanie Hamilton. For a few days I could see them both crammed inside the Live Rock if I shined a flashlight into one of the rock’s openings. But for the last 10 days I could not find a trace of her. At first I figured she went in there to molt. Molting takes a few hours. So, I figured give her another day or so to rest and she’d be back out. No dice. No matter how often I shined the light into the rock, all I could see was Melanie Hamilton. By yesterday I’d decided Scarlett must have died and I needed to pull the rock out of the tank, if only to remove her dead body for burial.

However, just before I did that, I shined the light into the Live Rock and lo, that’s when I saw Scarlett O’Hara. She was clinging to the roof of the cavity, and I could see her eyestalks hanging down. Since she emerged from the rock, all is back to normal. Scarlett O’Hara and Admiral Byrd run the tank and wander constantly, seeking food. Melanie Hamilton peeks out of her cave and pretty much stays out of sight. As odd as it sounds – I am so HAPPY!!! I really felt bad at the thought she died. Seeing everybody doing their usual thing, it’s like “aaahhh, back to normal.”

Oh – one last geek moment, a moment of pride for me. I did a 33% water replacement in the aquarium yesterday – almost double the 18 % change the time Admiral Byrd freaked out about the salinity, and more than the recommended 25%. I didn’t have much choice given that the water really needed changing. I added the water and held my breath, keeping a close eye on Admiral Byrd. Apparently, this time I did it right. The tank water was at a 1.010 specific gravity, and so was the new water I was adding. Not only that, but the other parameters were great : pH 8.0, total hardness (GH) >300 ppm, total alkalinity (KH) 300 ppm, chlorine and nitrite 0, and nitrates “okay” at 20 ppm. (I’ve been using the Jungle Laboratories brand Quick Dip 6 Tests in One strips). And Admiral Byrd? He just kept right on eating through the whole thing. Never once climbed the walls…he never even left the water. SUCCESS!!!

Now I’m saving my allowance to buy …. two land hermit crabs!!!! Stay tuned soon for their adventures.

And stay tuned…working on getting pictures of Admiral Byrd, Scarlett O’Hara, and Melanie Hamilton…if she ever comes out of her cave!