Diatoms/Brown Algae

[thommyboy12183]

Hi All,

I have done my research and read up on the "Brown Algae"/Diatoms i am seeing in my tank.

I used to see alot on my sand but i do not see much there anymore(however i do weekly 1/4 water changes and hover over sand). On the live rock i am starting to see some brown(almost furry like stuff growing on it) and on my glass i see the "Brown Algae".

The Brown Algae has started to really bloom in the past few days since i replaced my bulbs(Dual T5 with one 10,000 and one actinic bulb).

The tank is about 7 months old(so still new in the aspect of marine aquariums). I have two 800 gph power heads, 2 OC clown, 1 bi-color blenny, 1 cleaner shrimp, 1 marble fromia star fish, 1 condylactic anemone, 1 brittle sea star, ~25 hermits, ~15 snails). The tank is a 55G with the Reef Octopus 100 HOB protein skimmer.

I feed 1/2 cube of the frozen ocean nutrient omni/carnivor food once a day. and i dont see much sitting on the bottom of the tank ever.

I do run a HOB filter which seems to have its carbon filter pad fill with brown sludge regularly(which i change out every 1-2 weeks).

Is the brown algae more of the new tank still cycling or should i get rid of the HOB filter all together.

I do know i have high nitrates. with my test strips they are in the acceptable range of 20ppm which i know is still high regardless of being in the acceptable range. But i am not sure if this is still due to cycling(7 month old tank). Or something else. any suggestions on lowering the nitrates would be greatly appreciated.

I use a turkey baster to feed the 1/2 of cube disolved and it seems like everythign is eaten(with limits of some on last feeding being left) but i know the fish are hungry and they are vultures when i am feeding.

 

[nursedude]

What are your water parameters?
First, nutrients. The question is where are the excessive nutrients coming from? Do you use RODI water, how much live rock do you have: either your biological filtration is not able to keep up, or you are inadvertently adding excessive nutrients. Any changes, new fish, corals or live rock?

Second light, what is your lighting schedule. You may be running them to long promoting the growth. These types of outbreaks can be so frustrating. Hopefully we can narrow down the culprit and correct it.

 

[thommyboy12183]

The outbreak started yesterday(so i have not tested the water since then). However When i performed water change and tested on Sunday the parameters were as follows.

pH - 8.2
Temp - 80*
Specific Gravity - 1.024
Ammonia - 0ppm
Nitrites - 0ppm
Nitrates - 20ppm
Phosphates - 0ppm
55G with 50lbs live rock
1600 gph water flow total

My guess is the lighting may be my culprete i never got a timer so I turn the light on at 6am when i wake up(daily) and turn it off at around 8pm at night. Which now that i think about it is a long 14 hour day.

The algae bloom started when i replaced my bulbs so under the new more powerful bulbs too much light. what is the recommended time for lights on. I will pick up a timer today. ~10 hours?

 

[thommyboy12183]

I have always seen the high nitrates and i am not sure how to lower them. If i had to guess i always thought i was under feeding my fish.

 

[Patrick.S]

If your carbon is gunking up you might want a way to prefilter the water prior to it getting there. Maybe try something like filter floss that you can toss out twice a week. Get rid of the gunk before it gets processed into nitrate.

 

[thommyboy12183]

Also i do not have a RO/Di filter at home.
is it worth just getting rid of the carbon filter? or changing it out more regularly?

 

[RobZilla04]

Also i do not have a RO/Di filter at home.
is it worth just getting rid of the carbon filter? or changing it out more regularly?

Are you using tap or going to your LFS to get premixed salt water?

 

[thommyboy12183]

Tap water

 

[thommyboy12183]

Photos

 

[RobZilla04]

Tap water is likely the problem. Excess nutrients and dissolved solids are usually the culprit.

 

[nursedude]

It is hard to say one thing is the issue, this may be multifocal, but I do believe the tap water is providing excess nutrients to the tank. Unfortunately, by doing such frequent water changes you are adding to the problem. Now I am not advocating you stop the water changes, but I would recommend you know what is in the water you are using by using RODI water.
I think the lights just pushed the nutrient issue to a point that you now see a bloom. It is easy to blame the feeding as the "nutrient import" but all the biological life you have fish anemone, and crustaceans are adding ammonia to the water, which you see as nitrates. I also wonder if your skimmer is adequate. Once you switch to RODI do a 30 percent water change a couple times within a couple days. It takes these larger changes to remove the excess nutrients. Make sure you don't have dead spots that are collecting detritus in your rocks as well, these can be nutrient sinks. After these few steps test and see what you nitrates are.

My recommendations would be:
1. Reduce nutrient input: Use RODI water
2. Increase nutrient removal: More live rock, or larger skimmer, with a sump you could use macro algae.
3.Increase you pH to 8.3, carbon dioxide = carbonic acid which lowers pH, which algae thrive in. Minor I know but it might help.

Please let us know if things improve.

 

[thommyboy12183]

Hi All,

Thank You for all of your help. I have been working on lowering the water level. I don't see a RODI system in the near future as I don't think I could justify the cost of the filter/setup to my wife.

I will look into increasing my liverock after the holidays to see if that can help with filtering out some more waste. I have 1600 gph total water flow, I feel like if I put much more in there will be too much and it will disturb my sand bed(I currently see the occasional sand movement not too much but it was tough to arrange the power heads I currently have to not completely disturb the sand bed.

 

[thommyboy12183]

I do appreciate everyones help on this site.

 

[RobZilla04]

IMO if you continue with the tap water you will continue having these probs. If you compare the cost of travel and prepared salt water from your LFS and compare that to the one time cost of an RODI you can easily make the argument for a $100 unit to your wife. Then again you have to live with her, not me... Best of luck and merry Christmas.

 

[Hyde7278]

Buy RO water at Walmart if you have one close its $.37 a gallon

 

[thommyboy12183]

Thanks hyde thats a good idea