Help! Can't get this algae under control!

[Lerxt64]

Here's my situation:

I am relatively new to the hobby. Last year I bought an up-and-running 72 gal. bowfront with a crappy light (80 watts flourescent). 6 months ago I added a 4 strip T5 H/O. Right away I had a serious bloom of rust-colored algae. All over glass, LR, everything. It seems very fine & "powdery", easily blown off using a bulb syringe. From all the research I have done, it sounds like diatom. At the time, nitrates were really high. But now, 6 months and zero nitrates later, it's just as bad. I can't have the lights on more than 4 hours before this stuff coats everything.I do regular water changes. Have pretty good circulation, skimmer & filtration. I've heard silicates can be a contributing factor. The substrate is a mix of aragonite and marine sand(Estes brand). I have a few soft corals (polyps, zoos, etc.) that are hating life from this stuff accumulating. I use only LFS RO/DI for changes and top offs. My questions are as follows:
IS this Diatom?
Could the RO/DI contain silicates?
Could the marine sand contain silicates?
Are there other contributing factors?
Any help with this problem would be greatly appreciated.

[karp12]

Increase water flow in the tank, cut the amount of time your lights are on for a few days, add chemi pure to the sump. Did the trick for me.

[Bigtymez]

I had the same issue about 2 months ago. I found that no matter what I did, I was always getting brown powder all over the tank. I increased water changes to once a week (20% change) and did a thorough cleaning of the tank.

Things I learned:

1) Water changes are your friend. Make sure you blow off detrius and debri off of the live rock before your water change.

2) I removed about 10+ dead snails I had in the tank. This was contributing to a nasty smell, my water smelled awful. I only have a 24 g aquapod, so 10 snails dead = yuck.

3) I found in the back of my aquapod detrius had accumulated almost up to an 1" thick on the bottom. Just by blowing the gunk around with the pumps on, it circulated it throughout the tank. I then did a water change.

The next day my aquarium was clear and has been ever since.

[Chiefsurfer]

silicates CAN contribute to this. Do yourself a favor, and buy a $20 hand-held tds meter. When your LFS gives you the RO/DI, it should read nothing above 5ppm. If it does, tell them their membrane and DI is shot. If they do not change it, go elsewhere(or buy a RO/DI unit of your own). This is not proof-positive that the water is necessarily good, but anything above 5 will definitely be bad.

It sure does sound like diatoms. There are a few more things we know to accurately diagnose, and/or help you with your problem. 1, how much LR is in the tank? 2, How many fish, and what types are in the tank? 3, how often are you feeding? 4, WHAT are you feeding? 5, How often do you do water changes? 6, what did the tank and LR look like when you got it? 7, Is there either bio-balls, or any type of powerfilter connected to the system?

If there is anything else I did not think of, feel free to include it as well.

[bertoni]

You could be seeing diatoms or cyanobacteria or any number of similar microbes. Silica is not enough for any organism to grow: they all require carbon, nitrogen, and phosphorus to survive. Most of the pests we see require nitrogen and phosphorus from the water column, and the source of those nutrients tends to be fish food. Adding new lighting often produces such blooms. Silica generally isn't a problem, since diatoms are fairly tasty to many snails.

I'd siphon out what was easy to get, if any at all, and reconsider the feeding level for the system. The bloom might go away on its own in a bit, or the system might require more nutrient export: better skimming, a phosphate reactor, or growing and harvesting a macroalga are common nutrient export techniques.

[Lerxt64]

Thanks folks. my bio load is small- four fish no larger than 3 inches each for 72 gal. I have about 40# of LR. I change 20% each month. I alternate frozen Marine Cuisine (mostly mysis) and flake, ensuring it's consumed within a couple minutes. Skimmer is probably small for the tank - red sea prism, althought is does get about 3 cups/wk of gunk out. Filter is a HOB Aquaclear 110(500 gph), with sponge, floss & bio balls, which I clean weekly. Nitrates are 0. temp 80 deg F. Lighting is 4 strip t5, 216 watts, 2 actinic & 2 10k.

[Jhutto]

check amount of food and lighting cycle..make it shorter

[Chiefsurfer]

how long did you have nitrate issues for? Your rock can absorb nitrates and continue to leach them out for a LONG time. Also, try rinsing your frozen foods in ro water, then ditching the water, and feeding that way. Frozen(and flake) are known for high phosphates. There is nothing you can do about the phosphates in the flake, just make sure you never overfeed.

Lastly, even though you are reading 0 nitrates, I highly reccomend throwing in another 40 lbs of LR and slowly removing those bioballs in the AC. Make sure the sponge is cleaned every 2-3 days, clean in RO water, and make sure the filter floss is changed weekly.

Everything listed above are KNOWN to be sources of nitrates and phosphates, that will fuel algae. As I said, the rock can absorb nitrates and phosphates and depending on the length of their exposure, leach them back into the tank for MONTHS. This could be fueling it. That said, I have some diatoms from time to time, but my snails stay on top of it pretty good. Might look into a few more snails. My nassarrius and turbos eat it RIGHT up.

[bertoni]

Nitrate can't leach out of rock the way phosphate can. It doesn't adsorb onto the surface.

How much is the total volume of food going into the tank? Most of what goes into the fish comes back out, so the total volume is important.

[Chiefsurfer]

thanks again Jon, thought rock absorbed both nitrates and phosphates the same.

[Lerxt64]

thanks. I'll have to give the filtration more frequent attention. I feed only 1x/day, but I do notice lots of discoloration when i rinse floss & sponge. what do you think of carbon- can it remove phosphates?...about the snails- I've never had much luck with survival, even after correcting the nitrate problem. i do have 50+ small blue legs, a brittle star & small shrimps, I've heard hermits can gang up on snails for their shells. I have plenty of empty shells, though. does anyone recommend a good snail? Would the larger turbos be good?

[Chiefsurfer]

i love my nassarius, they do a serious sand-stirring job. Regular blue-leg hermits can get bigger and go after snails. I have heard that most DWARF blue-leg hermits stay very small, and tend to pose little threat. That said, In the 2 months I have had my tank up, I think my snail population has decreased some. It may be the endless supply of gorilla crabs I have(saw one about the size of a golfball last night) so im not sure what exactly is doing it. My turbos generally stay on the glass, and my hermits cannot reach them. The turbos clean most of the algae, but not I have squiggly patterns of algae, as they graze, a little is left behind.

If you can't get snails to live, I would start doing all other kinds of tests. Nitrates, phosphates, magnesium, calcium, etc. When they die, do they just sit closed on the sand, or do they just disappear. If they disappear, I would look predatory for an answer.

[spw4949]

From reading your description of your equipment my opinion is you don't have nearly enough current/flow.....a skimmer, small HOB filter & that's it right? In a tank that size(4') you should have a powerhead on each end of the tank, especially if your planning on adding more corals, increased flow/current may also help with algae........

[Lerxt64]

Forgot to mention 2 powerheads, although I think I need bigger ones. Crabs are dwarf blue leg. I think I'll try the snails again.

[spw4949]

What size/type of powerheads.......

[bertoni]

Carbon won't remove a significant amount of phosphate. It will remove some organic compounds, and can help with toxins and yellowing.

[Lerxt64]

Not sure about the powerheads, particles seem to move about pretty good, no dead spots.

[Chiefsurfer]

I think(hope) what spw was getting at is the fact that you want randomized flow, or as randomized as we can make it. The cheaper, more common powerheads are a very contained, directional flow. This is done by an impeller, like used in a powerfilter, then a straight tube to direct the water in the same direction. Even with great flow, you will find dead spots if the water continually moves identically 24 hrs a day, 7 days a week. The powerheads that use a "propeller" system, it sprays a MUCH wider path of water, and its not constant movement everywhere. Very tough to explain. I will post pictures as guides.

THIS is GENERALLY considered not a great type of powerhead, because the flow is too controlled:



This is generally considered a better design because of a better overall coverage of the water, and more randomized pattern:



AND THIS is a PERFECT example of the difference in an IMPELLER and a PROPELLER. Impeller on Left:

[Lerxt64]

Yeah, I have the top ones. I'll have to invest in better ones.

Thanks