20g AIO Simple Set up - No Skimmer or filter

[Shelley E]

Hi everyone,

I am newly back into reefing. I did have a larger tank many many years ago. Only just coming back to it now with a smaller tank,

20g simple set up with the mindset to go really slow on stock levels etc and see how I go. Been having trouble with some of my corals and recently (particularly after water changes even worse).

Livestock:
1 female percula clown (her partner decided to go for a late night carpet surf, even though I have a glass lid! there is a tiny gap around).
1 cleaner shrimp

Coral:
Green hammer
Green finger leather of some kind
3 Red BTA
Pink gonipora - Only new
Red Monti - Only new
Candy cane - that is very unhappy, much worse recently as I removed from frag plug and it got a bit battered.

Only have basic testing kits so don't have ability to check everything. Not as much stuff available over here in NZ, been a nightmare through COVID here too.

Params:
Salinity: 35ppt
Temp: 22-25C (swings around a bit, trying to dial in more. Might be our older house with limited insulation).
Nitrates: 0 or undetectable on two test kits. One seacheam one.
Nitrites: 0 or undetectable
Phosphates: 0 or undetectable
KHd: 8
Calcium: 300

Lights are a 24W LED set that came with the tank, running a little hygger wave maker (although turned off recently as was thinking corals were getting too much flow) ran on lowset power setting. Haven't run much media as everything seemed happy, then I knocked over my leather coral and since then the gonipora was closed up. Thought maybe toxins so added some activated carbon which only seems to have made things worse. Have removed again...

Hammer coral has never really been happy in the tank for last 4 months, even though oddly it doesn't seem to die and is slowly growing. It is never extended, always looks super closed up.
When it arrive it has burst from it's bag so it was never a good start. Only corals that really seem happy is the leather and the nems. Candy cane used to seem much happier when there was more algae around... My cleaner shrimp is always touching the goni with his feelers which makes it close up also.

Anyway here are some pictires, any help appreciated as really starting to feel stumped, only thoughts I had at this stage was the temp, or potentially not enough nutrients for some of the corals.

Tank when first set up back in August:

Tanks back in December when I got some new corals etc. Hammer, Nems and clownfish have been in tank maybe two months. New additions were leather, candy cane (free) and clown goby who unfortunately had a really sunken stomach when I got him. Didn't notice until I got home, wouldn't eat and was already on way out. By the time I got a shrimp hatchery up he was already gone. At this stage I also have some algae issues but these passed as expected. Green leather coral was in shedding stage when I got from LFS so I had to wait a while for that.

Any idea what kind it is? It's polyp extensions and size are much smaller than I expected.

This is how the tank currently is now (I turned off wave maker for Goni as it seemed to blast it too much which has caused my nems to go on the move....).
Monti coral really not happy, maybe there isn't enough light? Also got stung by moving nem...

Any help appreciated as really quite stumped... Possibly the temp swings? I've moved the heater to a different chamber with more space around it, might help.

 

[Timfish]

Two thiings stand out to me. first is it looks like you only used dry rock or fock that just had nitryfing bacteria added. I would try to fjnd some pieces of maricultured live rock to add cryptic sponges and other microbial stuff that can't be stuck in a bottle. See Aquabiomic's article.
Second, as you suspected your nutrients are low and your corals are starving. I'd add more fish and feed more.