are these dinos or diatoms (microscope)?

[krayzie]

Hi Guys

i have a 20G waterbox cube that has been up for about 7 months now and i have been battling this brown dusting of stuff mainly on my sand and glass for at least 4 months now which is below and covers most cracks and cevices of the sand bed and a film on the glass

under a microscope they look like this:

from scraping off the glass

i tried to scrape some off the sand:

my tank parameters are:

Ammonia: 0 - salifert
Nitrites: 0 - salifert
Nitrates: 9 - Hanna
Phosphates: 0.05 -Hanna ULR
Cal:450 - salifert/hanna
Alk:7.6 - hanna
Mg:1350 - hanna
SG: 1.026 - refractometer
Temp 26C

i use RO top off from the LFS which has tested to be 0 silicates (salifert). i have a crappy TDS pen it was showing around 9TDS
i use NSW from LFS every week for water change at about 30% (25 Litres)

tank inhabitants are
pair of clowns
1 x fire goby
1x tail spot blenny
2x trochus snails
1x nassarius snail
2x turbo snails

I feed a mix of frozen brine and marine mix with marine S pellets

i have 2x AI Nero 3's running 50% each
i am nutrient exporting with a bubble magus mini q running 24/7

dosing alk/cal/mag with red sea foundation for my
4 torch corals with 2/3 heads each
few mushrooms
1 blasto frag
3 hammer frags

my lighting is an AI prime 16HD with the following schedule

I have also noticed they disappear at night


any help would be much appreciated

thanks

 

[krayzie]

Adding some better quality pics i think
These were scraped off the sand

 

[krayzie]

I’m wondering if they are Amphora diatoms?

From here https://microscopyofnature.com/diatoms

https://microscopyofnature.com/sites/default/files/2022-08/Amphora.jpg

 

[krayzie]

Bump

 

[TheDuude]

I see both diatoms and dinos in those pics

 

[krayzie]

I see both diatoms and dinos in those pics

dang really? Which ones are diatom and which ones are Dino’s?

 

[TheDuude]

The cells that look like seeds are dino, the cells with more irregular edge and shape are diatoms. Both common in a young tank. Make sure your nitrates are above 5 and you have phosphate .05 or better In my experience