Coral placement advice for my 20g cube

[BangingBaking]

I started this tank around March and have gone through quite a lot, from Diatoms and Dinos to Cyano and a bubble algae outbreak (which I'm still combating with manual scrubbing).

I've been adding a few corals every month and have lost two so far in the journey: a mushroom that died the day after introduction and a Blasto that slowly receded away.

The rest of the tanks are doing pretty well and have grown larger.

 

I've added a bright green tenuis and a monti cap, which my friend gave to me as an SPS test frag back in August, and they have thrived well. So, I proceeded to add three more SPS (Stylo, Unknown tenuis, and Unknown Echinata?) in my tank yesterday.

These were cheap frags that came loose from my LFS's wild colonies and don't have the brightest color, but they look healthy (polyp extended) to my untrained eye.

 

The tank is getting quite full, and I'll try to stop adding coral for a while and wait for some of them to grow out. I have a few concerns right now and need advice on what to do.

1. Toadstool is getting too large - Should I remove it?

   This was about 1/4 the size when I bought it and was one of my first corals. It has grown very well, and my clowns love to chill in there every now and then. I've read online that they are highly toxic and could potentially kill other corals. The magnetic rock shelf is the only available space for it, and at this rate, it will start touching my SPS.  One of my favorite coral in the tank and want to keep it if possible
    

2. Gonio will eventually touch my Zoas and mushrooms - Does the placement look fine?

   All of the gonios have doubled in size over the past 4 months. In no time, the extended polyps will be touching the zoas and mushroom garden below if they continue growing. I've seen lots of tanks with zoas, mushrooms, and gonio being placed relatively close but was advised by my LFS that gonio will most likely kill them.
    

3. Stylo and hammer/gonio garden being too close - What should I do?

   Same concern as point 2; this newly acquired stylo was much larger than my expectation, and it's placed between my hammer and gonio coral.

   Will it be a problem in the future if they touch? If so, how can I prune these thick branches without a band saw? Will a bone cutter work?

 

Thanks in advance and will appreciate any kind of feedback.

 

 

 

 

Tank Spec

20G over flow

 

Lighting

Chinese 100W LED

・just copied some random profile from a successful reefer

 

Flow

・top left

130～1000GPH random

・Bottom center(for rock's detritus buildup prevention and overall tank flow) 

260GPH fixed wave mode(35% of 900GPH max rated) 

・Return

Random spin  nozzle shooting out gentle, thin steam

 

 

Filtration

・Marine pure Block(The large block, this occupies 30% of my sump)

・Filter wools

Replaced once a week

・Protein skimmer

Tunze Combline skimmer, I'm turning this off for quite sometimes because my tank gets 0 nitrate when turned on

 

So basically the tank runs pretty simple with just bio media and filter wools.

 

Water chemistry

・Salinity 1.026

・Alk 9.0-9.4(slightly higher according to my friend, but my salt mixes at 9.6)

・Cal 480

・Nitrate 5-10

・Phosphate 0.07

Everything is tested with Hannah checker, once a week.

 

Husbandry

・ 5gal water change weekly

・manual rock scrubbing bi-weekly

 

Additives

・Live phyto

culturing them in tupperware and squirt them out from 20ml pipette once a day

・Live pods

culturing them in tupperware2 and adding them bi weekly upon harvest

・All for reef  to maintain alk

 

🐟

・a pair of clown fish

・yasha goby

・6nassarius snails

・1 ring cowry

・4 trochus snails

・1Stomatella snail

・Fire shrimp