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It's funny how one of them blocked entrance to the cave by a shell of hermit crab

Temperature was 23,9 C in the morning, now 22,6 C (opened window). I haven't purchased coolers yet. Hope that 24 C was ok for them...

Ammonia 0 ppm
Nitrite 0,1 ppm (JBL test kit)
Nitrate 10 ppm
Salinity 1,025

photo_2021-03-12 18.45.59.jpeg
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Day 24

Removed carbon from filter. CupriSorb is still there.
I want to purchase a big canister filter (11 liter space for media) and fill it up with live rock to eliminate my 0,1 ppm nitrite.
Guys, do you think that BROs will catch camel shrimp ? Since almost 3 weeks, they didn't eat any of them. Big concern for me, as I noticed shrimps eating coral polyps.

Tried to make a trap with a food inside of a bottle - they don't get into it.
Hope octopuses will eat those evil shrimps, as I can not catch them...
I had some with a briareus. They lived peacefully together for months- then one day they were all gone!
It's funny how one of them blocked entrance to the cave by a shell of hermit crab

Temperature was 23,9 C in the morning, now 22,6 C (opened window). I haven't purchased coolers yet. Hope that 24 C was ok for them...

Ammonia 0 ppm
Nitrite 0,1 ppm (JBL test kit)
Nitrate 10 ppm
Salinity 1,025

photo_2021-03-12 18.45.59.jpeg
Was it a female who pulled the shell into the den? Some species just do that, but in several species the female does this when she’s making a brooding den. You’ll have to watch and see what happens over the next few weeks.
I think so, because it's bigger than the other one... Also, today I found that she/he released the shell.
Unfortunately today I had 0,25 nitrite. Probably due to skimmer working improperly. (video below) I suppose its because I've added 5ml of Seachem Prime(my tank is 130liters), that according to reviews may alter skimmer performance.
WhatsApp Image 2021-03-16 at 19.57.47.jpeg

Or maybe my new 11liter external filter that arrived yesterday was an issue, as live rock inside may have absorbed some waste particles from the water and they decayed inside.

Also, as I have purchased a new live rock - I fragmented it into parts to put inside, occasionally some living things like worms may have died causing contamination. (doesn't answer the improperly working skimmer problem)

Another reason probably is that yesterday I was also cleaning my skimmer (reassembled it and took out waste from rotor), but I don't think that's the case.

So, nothing changed except:
new filter with live rock
5ml of Prime
reassembly of skimmer.

As for now the skimmer is still working the same way... I'am really worried about my inhabitants
Maybe anyone has a clue what's going on ?

Did 15% water change today to address the Seachem Prime issue. However, if it is the root of a problem, 15% probably is not enough.
Removed some small fractions of live rock from the filter to prevent organics accumulate there.
Added DVH BioGro
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Solved everything by removing both filters. Nitrite 0 - 0,05ppm.

Seachem Prime wasn't the root of a problem - live rock inside the filters has been accumulating organics, preventing skimmer to work at 100% capacity. I just put all this live rock into the sump to ensure bacteria work on removing nitrogen.

Now CupriSorb is removed from the system, however I can put it into my overflow column instead of a sponge.

Also, I noticed that skimmer performance increases if I decrease the return pump's speed (2500l/h), so it's less than skimmer pump (1000l/h).
Arghhh... just tested 0,2 ppm nitrite... Don't know for how long octopuses can tolerate this level.

So, I'll add DVH BioGro bacteria supplement and probably 2,5ml of Prime.
So, here are NO2 tests for today:

JBL 0,1 - 0,2 ppm
API 0 ppm
Salifert 0 - 0,1 ppm / traceable amount
NH4 0 ppm (JBL)
pH 8,2 (API)
KH 9 (API)
Salinity 1,025 / 34
PO4 <0,05
Temperature 22,5 C

I have decreased fish & coral feeding and added another portion of DVH BioGro.
Put back two 540l/h canister filters (filled with live rock, CupriSorb and carbon) - they don't alter skimmer performance as opposed to 1500l/h one.

For me another indicator of poor quality water is my anemone, if it shrinks - it's bad. Now it's ok :smile:

Do octopuses need iodine for better health ?



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Also, I badly want to add juvenile clown triggerfish to my tank.

However I'am afraid that it will try to eat my blue rings (it likes inverts, as said on reef forums), so this probably will result in tank collapse due to tetrodotoxin venom be released into the water if an octopus dies. :smile:

So, if anyone had such an experience, please reply!
Bought 5 hermit crabs - as I add a crab to the tank, octopus catches it instantly, so hungry :wink:
Another blue ring is still constantly hiding in the same place, probably breeding. eggs... I bring frozen shrimp close to cave entrance, so he/she grabs it. Will look for hatchlings inside with a led torch today.

Added extra reactor with 250ml DVH All-in-One BioPellets (now have two of them).

Increased temperature to 24 C as 22,5 C is probably too low for lps corals, fish and nitrifying bacteria.
I will monitor octopuses more thoroughly next 2 days to check if they are ok with this temperature.

Moreover, I am changing my salt from Red Sea Coral Pro to Fauna Marin Reef Power, hope this won't affect BROs.
I'am considering to use CupriSorb and carbon episodically one day a week, as I suppose they accumulate organics that could be removed by skimmer instead.

Water specs for today:

NO2 0,1 ppm (Salifert)
NO3 10 ppm (JBL)
PO4 0,1 ppm (JBL)

pH 8,2 (API)
KH 9 (API)

salinity 1,025 / 34 ppt
temperature 25 C


Added Heteractis Malu anemone 2 days ago.
Today the male blue ring didn't respond to hermit crab put into the tank. However, he grabbed frozen shrimp. (probably I will find thrown away soon)
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Day 33

NO2 0,1ppm (Salifert)
pH 8,2

temperature 25,4 C

The male ate 3 hermit crabs this week so far. Also, I gave them frozen shrimp every other day, but of course, after a while I have found these shrimp pieces on the sand or on the pump.

From my observation I noticed, that male now tends to sit more in his cave. I don't know if it's related to an increase in temperature, but I found that in their habitat temperature varies from 21 C (south of Australia) to 29 C (Phillipines), so 25,4 C is probably ok. Female's behavior has no dynamics - always in her cave.

I'am considering to buy some live rock for them to have new places for hiding.

My display now:


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