I am out of idea fighting diatom

[oyf709]

My tank is about 2yrs old and I start to get this diatom problem back.
I think i was quite stupid to clean up my DSB and break down my DSB system after that.because I got cloudy tank for 2 days. I did that cuz i was removing all fish for ich treatment and try to improve my water flow by adding some pvc with drilled holes under my LR.
I put some active carbon in the tank for 2 hrs and my phosphate jumped from 0 to 3(so much of a promise for phosphate free, PS:blak diamon is the brand name). And I start to get this diatom problem going. I try to clean my glass and do water change right after but they come back and cover my glass after 3 days. I baught a phosphate reactor and drop my phosphate back to 0.2 and same thing came back after 3 days. I try to limit my lights down to 6-7 hrs and no help at all. My nitrate is around 5 and I only feed my fish about once every 3 days.
Now, I really need some solutions. Anyone had any exp wioth this? cuz from wat i know diatom should just burn out on themself but those i got just won't go away. I tried to get rid of them for 2 months now. But things just don't change much doesn't matter wat i do.


PS: I even drip Kalk during nighttime

my water is about the following
Ph 8.0-8.3
Nitrate 5
Phosphate 0.25
ammonia 0
nitrite 0
sainity 1.022-1.024
Alk 11
Calcium 450
silicate i didn't check but the phosban reactor should take care of it with the media removing both phosphate and silicate

[Brenden]

Do you use RO/DI water? If so you need to check your source and possible replace filters. If not then start. Phosphate is more than likely the problem. If you check your source water I bet it is higher than .25 In my experience any detectable phosphate in the tank is bad because the tank/algae is using it up so something is adding much more than the .25 you are detecting. Add to that phosphate test are not very accurate and you will more than likely have located your problem.

[oyf709]

sigh...my water is after RO/DI and It tested as 0 phospahte before i add them to the tank.
thatz why i have no clude wat i can do next...maybe i should just wait for 6 weeks or so see if it cycle itself back to normal.
Cuz my LFS told me when i vacume my DSB it made those nitrogen system break down and now they need to reform again.

[Brenden]

I have heard people say that LR will leach PO4 into the water. Since your tank is 2 years old, I would say that is not the reason if it is even possible that it could happen. Only other question I have is...You said you feed every 3 days. How much do you feed? more important what do you feed? If flake I would change to frozen. If you feed frozen do you rinse the thawed food with tank water prior to feeding?

[oyf709]

yeah i rinse them before feeding.. i feed the fish with myss and i usually watch after i oput the food in..if the fish can eat all those off i will get as much as possible out so..i pretty sure it wasn't the problem. And btw, my phosphate is down to 0 since yesterday but diatom came back in a hurry since..um..yesterday...i thought without phosphate diatom should burn out on themself?

[melosu58]

If you are talking about the dusty look on your glass that has to be cleaned off ,I still after 8 yrs have to clean the glass. I have to do it every three days. If this is what you are talking about then you will always have that problem. That`s what they make Mag floats for. If it`s what I think it is then you`re like the rest of us.

[oyf709]

um...the dusty stuff sure...but also those brownish thing? The more water flow i point to that location the more brownish thing will apear.
I am pretty sure those are diatom.