Diatoms or Dinos

[yabani]

Dear Reefers,
My tank is one year old, and in the past few months, brown build up has increased on the sand to a degree where it became appearing like MUD. What i did in JAN and FEB of this year is weekly water replacement by siphon'ing the sand from this build up. I was able to remove most of the browne build up, gradually, week after week. I did 50% water replacement, thne 40% then 30%.
However, I would enjoy a near bright sand color for a few days, until i see, in a 10-day period, this browne substance slowly and gradullay building up on the sand again!
Are these Diatoms? Dino's?

What can I do to stop these from coming back?

This is my configuration and setup:

1) 1000 litre tank
2) 3 shrimp, one blue-leg crap, one star fish, 5 chromis, and one mandarin fish, and one trochus snail.
3) 2x half-filled Carbon socks + RoPhos in socks in the sump.

Salinity is solid at 35.00 Temp is quite near 25 C
Alkalinity is low (4.x) don't know why.
rest like PH at 8.3
Ammonia 0.04
Phospahte ULR at 0
Magnisium at 1335

My Home has a centrlized Filteration system, plus my ATO feeds from a second 3-phase water filter.

Any tips?

do i have to remove the above fish when I siphon again?

 

[Kingsley_Reef]

I believe it’s diatoms

 

[Gumbies R Us]

Is the algae on the rock as well or just the sand?

 

[Lavey29]

You need to check your RODI for silicates.

 

[yabani]

Is the algae on the rock as well or just the sand?

There is slight algae on the last rock but recently grown. The rest on the rocks are no algae.

 

[yabani]

I believe it’s diatoms

What's the best solution other than water replacement?

 

[Lavey29]

What's the best solution other than water replacement?

The best solution is to determine the source of your problems. Diatoms go away on their own if there are no silicates available. You should get a cheap microscope and see what is in your sand. Bottomed out nutrients levels can lead to dinos also.

 

[yabani]

I started with Water Replacement with my 6-stage rodi water generator, upto 40% of the tank, and I did that by Siphoning the brown/colored water out of the sand. However, some remains float and then some settle on sand or rocks, and with time, they build up again.
Here is my most recent test results.

Take a look at the video.

Any thoughts?

 

[p1u5h13r4m24]

Hey it’s diatoms. Let ur nutrients build up your phos is too low. You need to have nutrients in the tank to support life otherwise algae’s will outcompete everything.

 

[Kingsley_Reef]

Your best solution is wait it out

What’s your TDS read?