Algae or diatom covering my sand

[twiddledog]

I have a 72 gallon reef tank. I have something starting to cover the sand. It started out as yellowish (diatoms i think) and now it is green and definitely getting worse. I am starting to have patches of purple as well. I am doing weekly 20% water changes with RO Water but it seems to be getting worse. Could it be the heat? The tank has been averaging 82 - 83 degrees with the warm weather.
Any ideas???

72 Gallon AGA Bow front tank with overflow
20 gallon long sump/refugium
Southdown sand live sand bed
2x250W + 1x150 Aquaspace Metal Halide Light
ETS EuroReef ES 5-2 protein skimmer
43Maxijet 1200 powerheads

 

[JayM]

You most probably have a nutrient problem. What are your nitrates and phosphates, and what is your water change source? Is it RODI water?
How old are your bulbs? And I think 43 powerheads are a lot of flow, so that's not the problem

 

[Apone]

I have had algae problems, specifically diatoms on my sand due to low alkalinity....

 

[twiddledog]

I have 3 powerheads, Not sure how old the bulbs are but they seem ok and I am using RODi water. Water quality is all normal. Nitrates are 0 not sure about the phosphate though.
Do you think a Diatom filter would help?
Thanks

 

[marco67]

how long has the tank been set up ?

 

[twiddledog]

The tank is well established but I purchased it about 6 weeks ago. It was broken down and reset up with all existing sand and water. I did make a huge mistake and used tap water for the first water change. since then I have been doing weekly 20% water chages with RODI water. Could it be a normal cycling of the tank?

 

[marco67]

If the tank was established then broken down it is no longer wel established. When breaking it down you probably/ definitly relesed lots and lots of traped organics, in the sand, under rock etc... combine that with the move and you are into a new cycle. Tap water may or may not be an issue, when you tested phosphates and nitrates ? Where are they?

 

[JayM]

If you forklifted the tank, it is almost certainly going to go through at least a mini-cycle. The good news is that it shouldn't be as bad as a new tank.....

 

[smcnally]

Sounds like cyano to me (the purple and green). All I can recommend is test PH, ALK, trates, trites, etc, and post the results here.

 

[twiddledog]

Nitrate is 0, Phosphates are 0 , Amonia 0, PH around 8.6, Nitriites are 0. My LFS told me it could because there was a scented candle buring in the room so I am going to stop the candles..wife won't be happy.

 

[marco67]

My LFS told me it could because there was a scented candle buring in the room so I am going to stop the candles..

OMG that's a good one Do you think they were serious or kidding (I hope)?

Nitrate is 0, Phosphates are 0 , Amonia 0, PH around 8.6, Nitriites are 0.

>Nitrate is 0<
is not surprising in a nuisance algae outbreak, don't be fooled into thinking there is not an excess of nutrients. Excess nutrients (which end up as nitrates) are probably being consumed and are never making it to the stage where you can get a test to register.
>Phosphates are 0<
It is very difficult to get an accurate test on phosphates ...which test kit are you using?
>ammonia and trite 0<
Good or you would have much more serious problems

I just re read your original post looking for a mention of your skimmer production I saw nothing .....what's coming out of that ER and how often does it make you Barf? at this point in the set up it should
also I found

Not sure how old the bulbs are but they seem ok

old bulbs more often contribute to a hair algae problem but as you go forward you may want to either find out how old they are or just change them for peace of mind. There is no real good way to tell by looking.

I'm am not a fan at all of chemicals, and I'm solidly in the "treat the cause not the symptom" camp but .......if you must and if you have exhausted all other natural approaches ...Boyd Chemi-Clean is a product that will work well here, just keep in mind if you go that route without changing anything else, the problem WILL come back.

Oh and BTW a stubborn tank can be stressful enough without having to deal with an unhappy wife please do yourself a favor and let her keep her candles
good luck
Marc

 

[twiddledog]

My skimmer is minimal..i just messed with it and it seems to be better.

I am beginning to see hair algae. I think I am in trouble.

 

[marco67]

Don't stress ...just cycling

 

[Scuba_Dave]

I burn candles all winter without any problems
Also a wood fire for heat all winter

Algae may use nutrients so "fast" that the reading is very low

Sounds like a cycle - how long was the tank setup originally?
That will tell you how many organics might possibly be in the sand bed (if ti was tirred up some in the move)

 

[twiddledog]

The tank was up for 2 or 3 years before I got it and moved it.

Also..my protein skimmer does not seem to collecting much at all.