Just another phase???

[sansouci01]

My 20 gallon reef tank has been up and running for about 8 months. I've gone through all the new tank fun things like diatoms. That went away and the sand cleared up nicely. Then, I had a real problem with bryopsis. Finally got that under control and the tank really started to look nice. Now, I am starting to see a greenish kind of diatom looking algae on the sand again. Any ideas or is this another phase?

 

[Sillyfishies]

Sounds like cyano.

 

[Sniperhank]

Sounds like cyano and pointing at a long standing nutrient issue in your tank since you've battled hair algae and now cyano.

 

[Leetch]

What do you have in your tank. What are your water Params, lighting schedule, etc. What does your cuc consist of? How often and how large are your water changes?

Sounds like something is going on causing bacteria and algae blooms.

 

[sansouci01]

Here's my info....I have virtually no bioload

1- Chromis
1- Serpent star
1-Peppermint shrimp
1- black spiny urchin
Handful of hermits and snails

0-amonia
0-nitrites
0- nitrates( of course that must be wrong because according to most posts on here it's IMPOSSIBLE to have no nitrates)
0-phosphates ( of course that's wrong too because according to most posts on here it's IMPOSSIBLE to have 0 phosphates)

calcium- 420
magnesium-1500 ( getting it back down after battling and WINNING my fight against bryopsis with TECH-M.
Alk-10.8
PH-8.1

I do 25% water changes every two weeks with water I make using ro/di from my filter...TDS out of the filter is 0 ( must be wrong because according to most of the posts on here it's IMPOSSIBLE to have 0 TDS)

My lighting is 4- T5 bulbs running 9 hours a day. 3 actinic and 1 50/50

Forgive me for sounding a little harsh but it can get REALLY confusing getting advice from sites like this. EVERYONE has a different answer or opinion

 

[Leetch]

I'm not seeing anything that would cause cyano unless the ro/di you are using is tainted somehow. But then I'd expect to see that in your water parameters.

I run a heavy duty protein skimmer that pretty much keeps my nitrates at or close to zero so it's not impossible. It's so low that many kits can't detect it. The more expensive kits can however read them but then again, if they are that low you shouldn't be getting cyano.

Bring your water to your lfs and have them test to be sure you are getting accurate readings.

Maybe try a different source for your water and watch your feedings. It could also be something in your salt mix but I wouldn't change everything at once. Deal with each piece a few days at a time to see if it gets better. If it doesn't fix it, move on to the next piece.

I would get the water tested at your lfs though just to be sure. Most will do it for free and hopefully they don't just use those crummy single sticks that can't read anything.

Good luck!

 

[BigRedsReefs10]

If you have enough algae / cyano it can cause you to test much lower than your actual levels. I agree with Hank, it sounds like you've had excess nutrients in your system for a while now. Just out of curiosity what test kits are you using?

 

[sansouci01]

I'm using red sea to test my mag,alk, and cal...API to test ammonia,nitrite,nitrate, phosphate. Here's a picture and yes, that is the actual color. My phone actually took an accurate color photo for once..

 

[aadair22]

I personally don't see any cyano? Get a Red Sea nitrate test kit.. Api can be very off with the nitrates

 

[Leetch]

Hmmm I'm not sure that's cyano. That does look like bacteria though. I'd still get a second test on you water to verify your parameters.

 

[Sniperhank]

Can you take a picture with the whites on tomorrow so we can see things better?

 

[Leetch]

Is it slimy to the touch?