Diatoms+Cyano

[Vgyoung]

I am having a Diatom and cyano bloom in my established tank idk what is causing this and am getting worried. MY sand is almost all brown and some cyano is forming... I do a 1g water change everyweek which in 1 month is about 10% of my water(29 gallon biocube) I have only 2 fish(firefish and clownfish) and i do not over feed I was thinking it could be my lights so im getting them changed within the week however idk what the cause is My tank will be a year in January.
Please help!

[Vgyoung]

Btw i run protein skimmer 24/7 and light cycle is 10 hourse

[cloak]

Changing out 1 gallon a week is not getting you anywhere on a 29 gallon tank IMO. You might want to increase this to 3-5 gallons a week and see what happens. Also, what kind of water are you using? (RO/DI) Maybe the filters need replacing. How old are your bulbs exactly? Replacing those might help as well. GL.

[Vgyoung]

I mean like doing 3-5 gallons is replacing nearly all the water in a month which is drastic right? 4 gallons a month is what was recomended to me the bulbs are 4 months old and yes RODI water It is read 0TDS

[Vgyoung]

I couldnt stand looking at it i took a turkey baster to that sand and now its white again but it will just come back :L

[Dan_P]

I am having a Diatom and cyano bloom in my established tank idk what is causing this and am getting worried. MY sand is almost all brown and some cyano is forming... I do a 1g water change everyweek which in 1 month is about 10% of my water(29 gallon biocube) I have only 2 fish(firefish and clownfish) and i do not over feed I was thinking it could be my lights so im getting them changed within the week however idk what the cause is My tank will be a year in January.
Please help!

A couple things seem a little unusual. I usually read about diatom blooms when the setup is new or when the owner adds silicate to encourage sponge and diatom growth. The second unusual thing is that a diatom bloom is happening this late. And finally, diatoms and cyanobacteria blooms at the same time? Tough luck. Are you certain about the identity of these algae? Post a picture.

Nutrients are the prime suspects not lights. How are the nitrate and phosphate levels? Post the numbers to stimulate further input.

[Vgyoung]

It is the same... and you can have tons of nutrients but without lights they can not grow which is why lighting was a concern but anyway phosphates are .1-0 (color is so close I cant tell) and nitrate is 0 I was thinking silicates as well but idk what is causing them

[Vgyoung]

I added pvc pipe to help the protein skipper stand up could that leach silicates if so how long?(just came to mind xD)

[droog]

I mean like doing 3-5 gallons is replacing nearly all the water in a month which is drastic right? 4 gallons a month is what was recomended to me the bulbs are 4 months old and yes RODI water It is read 0TDS

Think of the PWC as diluting pollutants like nitrates & phosphates. 10% weekly, 20% bi-weekly or continuous are all viable strategies.

Well covered in detail here

http://reefkeeping.com/issues/2005-10/rhf/

-droog

[Shawi]

I mean like doing 3-5 gallons is replacing nearly all the water in a month which is drastic right? 4 gallons a month is what was recomended to me the bulbs are 4 months old and yes RODI water It is read 0TDS
Changing 5 gallons per week would replace 53% of the water per month.

1G ~13%

http://www.hamzasreef.com/Contents/Calculators/EffectiveWaterChange.php

[Tahiti]

I had a 29g bio cube and did a 5g water change a week.

[Vgyoung]

my question still stands is the pvc pipe leaching silicates

[ScienceAchieved]

my question still stands is the pvc pipe leaching silicates

I didnt measure the silicates, but 24 hours after I put a pvc burrow for a mantis shrimp in my tank, I got the most rediculous bloom of diatoms and filamentous algae ive ever seen. I doubt it was coincidental, I had very little algae before the pvc went in, tanks been up for 5 months.

[shesacharmer]

I'd turkey baste the entire tank, then do a 10% water change, then do three days lights out with any curtains drawn (no need to shroud the tank). Blue lights only on day 4 then reduce lights to 8 hours commencing day 5. That will get you started. Then I'd start doing 10% wc twice a week until until you get a handle on this. That's what I'd do. I don't know about the pvc causing a problem. I ran a QT with alot of pvc pieces in it for three months with no problems.

[Vgyoung]

then again qt tanks have no live sand xD Thx though guys im gonna try that @ sheac

[Vgyoung]

@science same with me 0 anything! tank was looking great decided i wanted skimmer so i added pvc pip under it and bam silicate haven i guess xD