Any idea what this is?

CaBrowne · Jul 21, 2018

I have a 3 month old 75 gallon aquarium. About a week ago all of this showed up overnight. I thought at first it was just diatom bloom but now I'm not so sure. Went and got a cheaply microscope and the results still confuse me.. Is this dinos?
Here are my parameters
75 gallon with 20gallon long converted to sump
Around 95 lbs of live rock
I run 2 Bloomspect 165w LED blues at 30% whites at 15%. I run blues from 8am to 10pm and whites from 10am to 8pm. Have a refugium in sump that I run full spectrum bulb on alternate 10 hour schedule.
I run a bubble magus 5 protein skimmer.

Temp is at 78
Salinity at 1.023
Ph is 8.1
Ammonia at 0
Nitrites at 0
Nitrates at 10ppm
Alkalinity at 143.2
Calcium at 300

Did a 20% water change 3 days ago because nitrates were at 30.

Anyone have an idea on what I'm dealing with?

Idoc · Jul 21, 2018

Looks like diatoms.

Zeal · Jul 21, 2018

Diatoms, hows the flow around the tank?

I see some algae with bubble tips on the top right aswell. Also you have ALOT of a rock in there for a 75G

CaBrowne · Jul 21, 2018

Zeal said:
Diatoms, hows the flow around the tank?

I see some algae with bubble tips on the top right aswell. Also you have ALOT of a rock in there for a 75G

Flow is good. I have the return 800gph that comes out two ports. Two koralia 425s on either end and a jeabo that I have set to about 1000gph at one end angled across the back. The first pic is misleading it's not a pic of the whole tank. Just of one island because I was trying to get a close up of the stuff growing. Here is a pic of the whole tank.

Zeal · Jul 22, 2018

CaBrowne said:
Flow is good. I have the return 800gph that comes out two ports. Two koralia 425s on either end and a jeabo that I have set to about 1000gph at one end angled across the back. The first pic is misleading it's not a pic of the whole tank. Just of one island because I was trying to get a close up of the stuff growing. Here is a pic of the whole tank.

much better I was gonna say...

Whats in the bucket?!

DEWreefing · Jul 22, 2018

Diatoms for sure just make sure you are using rodi water so silicates are not in your system which feed diatoms.

Dennis McGrath · Jul 22, 2018

I think every new tank gets diatoms. Maybe yours just took a little longer? It will pass.

40B Knasty · Jul 22, 2018

Going to agree with the consensus of it being diatoms and it will just pass. It is the 1st ugly phase after cycling. No need to find a miracle cure for it. Fighting conch is a cool little critter to have. It helped with mine. Plus they are kind of a chunky snail. So when they drag themselves along the bottom. That also helps.

Ron Reefman · Jul 22, 2018

This is an issue so many that are new to the hobby don't realize. Your tank is cycled, that simply means you have the bacteria you need to process ammonia to nitrite and then to nitrate. That isn't anywhere close to being the end of the development process in becoming a stable system. It takes 6 months at the bare minimum and sometimes more than a year. There are diatoms, other algae blooms, bacteria blooms that are all possible before things are mature. Some may be really dramatic and look really serious and some may never happen. Every tank develops a little different. Give it time. And it may get worse before it gets better. The diatoms need to use up whatever it is they are feeding on, then they will reduce down to a manageable or even invisible level.