[davidcmarkham]

I have been fighting (successfully, I think) a cyanobacteria problem for the last few weeks. It was the deep purple stringy kind and it really started growing (mainly on the substrate) when I got my new 285W Icecap VHO going (about 7 hrs a day, any more than that was VERY noticable on growth). Tank (36"x18"x24" deep - 75 gal) had been running for 4 months previous to getting the new lights with 75# LR and 2-3"crushed coral substrate. Now that purple stuff isn't around but a small amount of dark green stringy stuff is, and a large amount of this red patchy stuff is also. This red stuff appeared all over the tank instantly the day after the purple was gone, it did NOT start small and spread. Every 3 days or so I use a soft bristle brush and brush it off as much as I can (I think before it gets stringy, but I am not sure that it gets stringy becuase I am trying to not let it get to that stage.) I comes off pretty easily, but since the LR is porous, I can't do any kind of thorough job. Coralline alge is starting to spread a little, but as of yet, there is only a little of it.
Since it comes off so easily (I use a very soft brush and it is no problem) and isn't really getting worse, it seems that this red and green stuff is a less hardy variety of cyanobacteria that is now able to compete with the purple stuff gone. Phos is 0.1, but continued use of phosphate sponge (48 hrs at a time so it isn't leeching back in) doesn't take it lower so I think my test might no be able to read lower than that, and NO3 is down to less than 10 ppm, NH3,NO2,pH, ALK are all 0 or normal range. I have a 5 gal sump with bioballs and a skimmer that is producing skimmate (don't laugh, it is a seaclone - from what I have read, I may have the only one ever made that actually skims - but I now wonder if it's just too small.) I am using Purple up periodically and the Ca is about 450-500. I only have 3 little fish so I feed every other day to help control nutrients in the water.
I have pictures, but the forum won't let me attach anything yet (sorry). I would like some input as to whether this is normal "new tank cyano bloom" or if this is something else and I need a new strategy with it. I want to get the tank ready for coral to go in. And if you recognize the white dots in the last picture, I am curious what they are. They weren't visible before the colors started growing so they might just be sites on the rock that nothing sticks to, they don't brush off either. I can't connect during the day so I will answer any follow up questions tomorrow night. Thanks for the help, Dave

[charlie]

First off
glad to have you!

A couple of things, when you brush that stuff off the rocks, are you siphoning it out of the system? This will also help rid your tank of it's excess nutrient problem. How often and how much water do you change?

The 2-3" crushed coral bed is going to be a nutrient sink. Your Phosphate readings are low because the algae is using it for food. Get rid of the bioballs too, in the long run they are a nitrate factory.
What type of flow do you have in your tank, it sounds like you don't have enuf to keep the excess nutrients in suspension, therefore the cyano.
Personally, I think you would be better off with something like aragonite sand for a substrate, and a better skimmer, but this is just my opinion.

Hey, we have all dealt with this stuff, so don't feel to bad. The start of coralline growth is a good thing, but we need to get the problems fixed before you start adding any coral. HTH

[davidcmarkham]

Thanks for the reply, here are some re-replies.
1. I siphoned out the purple cyano, but this red stuff is more like powder when it comes off so there is no hope of siphon. That being said I will try it anyway and change out my filter floss.
2. recently I am changing 10-15 gal every 10 days or so. This is more frequent than in the past due to trying to get the cyano killed.
3. flow comes only from my sump pump rio+ 2500 which the curve shows 530 gph. I have been thinking I need a powerhead for more flow. any recommendations on flow and placement?
4. I have heard others say that bioballs are a nitrate factory but no one explains why. I didn't think I had enough live rock to be enough on its own so the bioballs will be swing bacterial growth area in the event of too much dissolved organics. If my skimmer is too small, then I could see that the bioballs would get the organics before the skimmer, but if the skimmer is sized properly (which i don't know how to guess the right size other than what is claimed by the manufacturer) how do you know how much live rock + bioball area is enough or too much? I have a 4 year chemical engineering degree, so the more detail you can give me the better -- I can handle it -- I almost understand ninong's dissertations (ha ha)!
5. please recommend a good kind of skimmer -- not too expensive if possible
6. why is crushed coral a nutrient sink -- porous?

I appreciate you help. and this forum, I can't even log into reefcentral.
Dave

[Samper]

A couple of Seio or Maxijet powerheads will get you more flow. IME the maxijets tend to send stray currents in the water after a while and the seio's have not done so for me. The MJ is also louder and doesn't put out a nice broad flow pattern that the Seio does.
Bioballs are a nitrate factory because the bacteria breaks down everything into Nitrates but there is nothing to remove them from the system after that.
IMO you cannot have too much LR as long as you're getting good flow through it. Live rock is your systems best natural filtration. With a deep sandbed and a refugium and a good skimmer you will have better success. On the skimmers, most people say to cut the factory specs in half and that's about what it is rated at. For instance a 100 gallon skimmer will maybe skim a 50 gallon tank but even this isn't always true. The seaclones won't even skim a 5 gallon tank....they're just junk. If you're looking for a cheap one that works pretty good the coralife skimmers will do the job. There are some mods out there that are easy to do and make all the difference in the world. A few friends of mine in my area run them on some magnificent reef tanks and after the mods the skimmers work great.
Crushed coral is a detritus trap. The wastes fall into it and destroy your water quality due to the amount that is breaking down/building up and not being removed. A sandbed will slowly break it down as it moves through the layers or your flow will blow it off the top for removal by the skimmer. I hope this helps.

[davidcmarkham]

Thanks, that does help. Since I am not sure I have enough live rock, I might start experimenting with how many bioballs to have in the system when I get a better skimmer. I have heard the corallife skimmers are pretty good, what if I want to go a step better than that? I went with the seaclone not knowing any better becuase it was cheap, I hate to go with the next cheapest even if it is better. Is it a lot better, and recommended, or kinda better for the same money.

How much total flow do I want in the tank. Is there such a thing as too much flow? I ultimately want coral to be very happy - my wife is even excited about the coral.

Lastly, thanks for the explanation on the crushed coral. Since the sand packs more densly, ditirtus won't get trapped - am I understanding that correctly? What if I got sand and stuffed it down so it filled the free volume between the coral pebbles (and laid down an inch or so above that, which I think you are saying is beneficial) would that fix it, or is there some reason to remoce the crushed coral. Obviously time and money prevent me from automatically wanting to do that.

Thanks again for your continued replies to my endless pestering...you're all worth your weight in gold.
Dave

[weez1959]

I'm in the same boat with the crushed coral, real crap trap! If I was to tear everything apart, take out the CC and replace it with sand and put everything back in, would I have an ammonia spike/cycle to contend with? Or could I put my fish back in right away?
Sorry for butting in on your thread but I figured the answer here might help you too...

[rjs5134]

I had the same problems in my 65 gallon... I increased the flow with a Seio, removed the crushed coral and added a My Reef Creations MR-2 skimmer. I have nothing to complain about now. I will add sand soon, but have a bare bottom right now. And no I didn't see a noticeable spike Louise.

Rob

[Reefland]

Hi Dave,


You will be able to post pictures now (your registration was never confirmed).

weez,

Yes, your going to have some re-cycling to do and therefore I would not add fish right back to the system. The tank is going to be very cloudy as well. In this case, I would set up a temp tank to hold the fish for af ew weeks while things settled in your display.