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Cuttlefish tank cycling.

Dec 7, 2008
Upstate NY, USA
Recently started a cuttlefish tank and it was suggested I start a thread here. Right now I'm 10 days in. I added 80 lbs of liverock to my 40 gallon breeder tank on May 4th, along with about an inch of sand. Ammonia is currently at .25, pH 8.1 and salinity is 1.024. I ran the skimmer for the 1st week, but have turned it off as I felt like it may have been unnecessary to run it so early. Thoughts on that appreciated.

So a few notes/updates. All equipment is running fine. I've been turning on the T5 lights for a few hours a day here or there although I know that's not necessary. I haven't tested the water again since last weekend, but going to do that again shortly. Hoping for some nitrites. Have had the skimmer off for most of the week. The liverock was purchased from my LFS's curing tub and put directly into mine, with about a 20 minute car ride. There are starfish, tube worms and other stuff definitely still living in there, so I'm wondering how much of a cycle I'm going to really see.It'd be nice if some of those critters survived. I have noticed a slight tinge of brown algae on some of the rocks, so I'll probably shut the lights off for good for awhile.
pH 8.0
Ammonia 0
Nitrite .25
Nitrate 10
Salinity: 1.025

So, pH is a little low, may need to rectify that. I did not expect all the ammonia to get eaten up so quickly, esp since I've been throwing fish food in there every couple of days. I suspect turning the skimmer off helped.
Today I noticed a small bristleworm and some tiny skittering microorganisms all over the glass (pods of some kind, maybe?) The fan worms that hitchhiked in on the rock seem to have all survived for now as well, although I have no idea what they are eating. About half the tank is covered in brown algae (I assume from the nitrate and/or phosphate spike). I fitted a filter sock in the sump last night to help with some of the micro bubbles (since I don't have any baffles in there) and it seems to have worked. There is also a bit of what looks like hair algae forming in the upper righthand rocks. A single large nerite snail and a single blue leg hermit crab seemed to have also survived and seem happy to pick at the new algae. I'm still concerned over the low(ish) pH, and since I used sand and not crushed coral, I am thinking of going and getting a small bag of crushed coral and putting it in a filter bag in the sump to see if it helps.
Weekend updates: So, nitrites finally came down to 0, and nitrates only shot up to about 15 ppm. My LFS was having a huge sale on livestock this weekend so I picked up a few hermit crabs and snails. Hopefully, fingers crossed, they do OK. (They seem to have made it through the first 24 hours). I will probably be doing a water change in a day or two. Also, this morning (Monday) I noticed a bazillion tiny free-swimming little shrimp of some kind.
The shrimpy things I've been told are a type of 'pod' too. I've also been told they are good things, yay! Mine come and go. Your tank pic reminded me to get a thermometer (ty!). Looks good, as far as I know anyway!

What other sorts of things can one add to a sump? I was looking at set ups that include refugiums, but my sump doesn't have one... but I've also noticed people adding stuff to their sumps which makes me insanely curious.
My sump is really basic. I used a 20L, and I don't currently have any substrate or anything. It houses a heater, the vinyl tubing that goes from the hard plumbed input, and output, and a leaky, but effective CPR bakpak skimmer. I also have a bit of chaeto in there, as the sump gets a fair amount of ambient light. And I just fitted a filter sock over the input and weighted down the tube with a chunk of lava rock.
Catch a few an put them in a glass and photograph? Mysid are notoriously difficult to cultivate but a few members have been able to have a small number continue to reproduce by separating the young from the adults - sadly, not enough to use as food for baby cuttles. If they totally disappear in a week or so, then that seems like a good guess. There are several "pods", Wikipedia mentions that some forms of the smaller copepods are free swimming.
Interesting set up - the add ons to the sump systems can get quite involved. The youtube videos of peoples' elaborate set ups are rad. Would you mind taking a photo? I'm totally new and curious.

The main heater for the tank can go in the sump?
I was reading about how to fortify our lid, and the wire for the heater posed a little problem for us. Our heater is in the tank. We left it because the LFS put it there, figured it must stay in there.
The next phase for us is to get a protein skimmer and to fortify the top, a couple little odds and ends, and live food... but we're ready to get an octopus after it is all in place.
Definitely put your heater in the sump. You may need to kick it up a little but octopuses don't understand being burned. Jacques Cousteau was intrigued by this and mentioned that they had to stop their "experiment" as it was clearly cruel. Before dive lights, underwater photography and night dives used torches (don't ask me how that worked :biggrin2: I have no clue). As I remember it (Octopus and Squid, The Soft Intelligence - Highly recommend reading - out of print but available used quite inexpensively) the dive team wanted to see how the octopuses would react to the torch and heat since it was something they would not experience in the wild. The octopus was curious and did not flinch away, resulting in a burn.
Here's a pic from when I was still putting things together. The skimmer leaked so was not set up on the back like shown. I'm not a huge fan of the stand but it was what I had. I think eventually I will replace the stand with something better (ideally I'd like to try building my own but my carpentry skills are nil at this point.) I'll definitely second putting the heater in the sump, too. Will try getting a pic of the tiny shrimp soon.image.jpg
Rocco wanted to build a stand, I support the idea (he built stage set ups in college) it was winter when we got the tank... so building wasn't exactly an option at the time. We also wish ours was not against the wall. We placed our rock not as a pile in the middle and we would like to see the back of our tank. Maybe with a water change, we can somehow move it. Seems like a ridiculous idea at the moment. Can I also put my skimmer in my sump? You have yours in the tank still? ... you're setting up for cuddles... less worry about escaping lol.
Skimmer is currently sitting smack in the middle of the sump. I snapped one of the skimmer's pipes while trying to tighten and stop a leak, but it's fine, it looks better down there anyways. I'm starting to get flecks of some kind of bright almost neon pink growth. It doesn't look like cyano but not sure it's coralline either.image.jpg

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