[Featured]: Octoproofing glass tanks

[qiazopus]

Excellent points, I appreciate it so much thank you!

Yes it's been pretty challenging to adapt to a facility that isn't catered for such work! The tank walls are so heavily crusty with salt remnants I doubt anything can stick to it. I'd try scrubbing them on my next visit but then again with glass tanks I can't use harsh sponges. I might try duct tapes or something, fingers crossed it'd at least stick a bit.

I'd skip the mesh then for the adults, and ask for 2mm slits.
When the eggs are about to hatch, should I add mesh (I bought 200micron mesh) to the heater cage? My main concern is whether it can affect heat dissipation. The hatchlings are about 4mm in length. I reckon I'd change the mesh regularly as you've advised before, for both the cage and the outflow pipe. Will it be an overkill to also add in the commercial heater guards (that the heaters sit in usually) on top of that cage?

 

[pkilian]

The salt creep can probably be taken care of with a wet towel if you use it to soak the salt and then wipe it away. It's frustrating that the facility seems to be under poor care but I suppose you will have to do what you can with the setup you have.

I would do a test run of the heat dissipation with the mesh around the heater cage, with one temperature probe next to the cage, and another on the far side of the tank, near the drain. I don't expect the mesh to give you any issues with heat dissipation but you won't know for sure until you measure the water temp.

Having mesh on the drain screen sounds good to me as well. It will probably have to be cleaned every few days. You can probably just use an old tooth brush to scrub the bits off the mesh without having to remove it from the drain. Depending on how dirty the screen around the heater cage gets, you may have to do a more thorough cleaning but it's hard to say for certain until you have everything set up and see how clean the water is.

I don't understand the part about heater guards. Would you be putting them around the heater? Do you have a photo?

 

[qiazopus]

I'll give that a go! Yes completely agree, that's partly why I've been planning this for so long haha. I just hope the octos will be happy with the modifications!

Sounds great, I'll do that in my test runs and scrubbing routine!

What I meant is to use heater guards like these: Aqua One Heater Protector 25 To 300W | Aqua One | Petbarn and then place the protected heater in the slotted cage that I designed earlier for extra protection - or an overkill?

Do I need to adjust the height of the air stone in the tank and transport buckets? I was told that the air bubbles can be detrimental to the octopus as it can enter the mantle and kill them!

 

[pkilian]

Hmm, I think I would be more worried about the heater damaging the housing cage rather than the animals. What material is the slotted cage going to be made of? How warm will you keep the water? What is the temperature of the water that enters the tanks?

If you are making the slotted cage out of PVC plastic you will probably be fine. Its melting point is somewhere between 250-500 F depending on the specific makeup of the material.

There is a chance that bubbles from the airstone could enter the octopuses mantle but it is extremely unlikely. I would be more worried about the bucket airstone than the tank, especially if the airstone is in the slotted cage with the heater. How long are the animals going to be in the transport buckets? Realistically, as long as the airstone is agitating the surface of the water it will be doing its job properly, so it doesn't need to be deeper than an inch or two from the surface to be able to properly off-gas the water.

 

[qiazopus]

The slotted cage is purely made of acrylic, I checked that acrylic has a melting point of 320F. The seawater that’s coming in will be during Spring (max 68F) and maybe summer (max 72F). I’ll be setting different tanks at different temps, mainly 66F, 75F and 81F for climate change simulation.

Btw the ‘slotted cage’ I’ve been referring to is the one I designed and attached a picture earlier. The ‘heater guard’ is the one in the PetBarn link. Maybe having an additional heater guard may protect the cage? And the heater guard-in-slotted-cage may help protect the animal?

Would duct-taping the air stone so that it’s just around the water surface be okay for both the buckets and tanks (taped to the slotted cage)? It’s a 20L bucket so I might fill half of it then secure the lid with Velcro. The journey itself is h but I’ll check them every hour or two. So plus rest stops, they will be on the vehicle for about 10-12hours and I’ll be bringing extra tubs of seawater in case of inking.

 

[pkilian]

I don't think the heater guard is necessary for the safety of the acrylic box, and the octopus is going to reach in and mess with the heater regardless of if the PetBarn thing is there or not, so its down to your budget I guess if you want to include it or not. It won't hurt but I don't think its strictly necessary.

Duct taping the airstone should be fine to secure it in the proper height in the tank. I would tape the air line to the outside of the tank in order to keep it in the right spot.

For the bucket transport- I would fill the buckets as full as you can to prevent sloshing, that is what will cause inking the easiest. Either do that or pack your octopuses in bags that are completely full and put the bags in the buckets to prevent sloshing in that way. For airstones, I would drill a hole for the air line in the lid of the bucket if you can and then you can duct tape the air line to the top of the lid to keep the air stone at the right height. I've had plenty of octopus shipped to me overnight and they will be in about 3-5 gallons of water for 18-24 hours with no airstone and no problems. Bimacs are pretty hardy but your mileage may vary.

 

[qiazopus]

3 more days before collecting the octokids!!

Preparations are in progress and almost done - thanks to all your advice!

I guess the last thing would be that the seawater where the octopus comes from has a salinity of about 44ppt (a unique group living in a shallow bay!), while my tank facility has incoming seawater at about 37ppt. My supervisor said to remove half the 44ppt-water from the bucket, and refill the half with the 37-ppt water for acclimation but I wanted to confirm if that's okay.

After all the driving it'd also be pretty late, so wondering if it's best to acclimate them in the tanks overnight instead of the buckets, while noting that the tanks are currently set to about 1L/h flow rate (tanks are 20L size but have about 18L water). I'll have oysters, mussels and crabs waiting for them in the tank too to help with their acclimation!

 

[pkilian]

Exciting!

Do you have a way of adjusting the flow into the tanks that you plan to put the octopuses? What you could do is put the octopus and their bucket of water into an empty tank, and slowly drip in the makeup water overnight. This wouldn't usually be a good idea for a recirculating system, but if you have a flow-through setup at the research station then you shouldn't have any problems. I think combining half the 44ppt and 37ppt would probably be too drastic a change in salinity for your animals, especially because the temp and pH of the two different waters likely wouldn't be the same either.

In an ideal world, what you would do to have the easiest acclimation for your animals would be to:
1) Pour the transport water into an empty tank on your system and add your octopus to that water. Leave the heaters in the tank off for the duration of acclimation if the water coming from the makeup lines will be in an acceptable range.
2) Make the flow into the tank a steady drip. I like to have individual beads of water coming out of the makeup line and have them almost connecting into a steady stream but not quite that fast. I can send a video if that would be helpful. Additionally, double check the temperature of your transport water and the makeup water coming from the line. Depending on the difference between the two temperatures, you can adjust your acclimation time accordingly. A good rule of thumb is to only change the water temp by 1 degree per hour, but this varies on the species of animal you are working with.
3) After about 1-2 hours, increase the flow to a small but steady stream of water so that there are no longer individual beads.
4) After another 1-2 hours, increase the flow to a normal rate.
5) Depending on the current temperature of your tanks and the temperature you want your tanks to be before you start your experiment, slowly adjust your heaters (again, about 1-2 degrees per hour).

Now, I realize you will be getting in with the animals very late, and probably don't want to be up all night babysitting your octopus acclimation, so what you can do if you are pressed for time is:

1) repeat step 1 above
2) set the flow from the makeup line to a small but steady stream
3) leave for the night and come back in the morning to fuss with the heater and temperature acclimation.

Additionally, I wouldn't put anything other than a coffee mug or some kind of den in with the octopus while they are acclimating. Crabs and such could bother the octopus during acclimation and make the event more stressful. I usually wait until the next morning to feed my animals after acclimation.

Good luck! Let me know how it goes.

 

[qiazopus]

So it's been a rough week transporting the 12 octopus (all females). I was really unlucky to meet with hot weather and severe wind (accompanied by dust haze that didn't help with the temp) in the only 3 days that I'm collecting the octopus. I placed car shades all over the buckets. We had them at 15degC, and it was 23degC after a 9h trip back to the facility. I didn't use all of the water each octopus came in as most of them look cloudy, so I used half the spare seawater I brought from the collection site. And then let the line drip overnight as you've suggested. 6 octopus unfortunately didn't make the trip, I was so devastated... The next morning (Day 2) another octopus died.. And today (Day 3) I noticed two of them don't look good on the eye area - let's call them Oct A and Oct B.

Oct A looked weird since Day 1, arms are curled and it was resting upside down (funnel side facing up). It looked as if it's senescent but no eggs were laid. On Day 2 I gave one mussel, but the mussel is dead (the company gave me dying mussels when I asked for live ones..). Today, I saw the right eye area being swollen, the eyeball can't be seen and it's a white round spot where the eyeball usually sits. I also saw the other eye going downwards and an hour later it also became just a white round spot. It still moves about but the arms are so curled.

Oct B is a big girl and very active, generally looking healthy and curious since Day 1. I also gave a mussel on Day 2. But today I noticed the left eye has a bubble... I removed all the mussels as I learnt from a casual chat that bacteria grow fast in dead mussels (I mentioned that repeatedly to my collaborator but she didn't mention anything about it being harmful; she has never worked with octopus before). I immediately changed out the water to fresh ones and gave oysters instead.

Is there anything I can do? :'(

 

[qiazopus]

OctA has sadly passed today... OctB's skin is looking worse with a large white patch and more obvious translucent patch around the left eye.