algae problem

[cmccartt]

I have a 75 gallon reef tank that has been set up for about 3 years. Recently, I began to experience a problem with red slime algae (cyano). I would remove it from the rocks and find that it would return the very next day. I treated the tank with UltraLive red slime remover. This seemed to do the trick but shortly after the treatment I started experiencing a problem with green hair algae (which I have never had). I broke the tank down and removed all the LR and scrubbed it removing all the algae and did a 40% water change. The tank improved for a short period of time but now I seem to be experiencing the same cycle all over again. My nitrates test 0. Is this a phosphate problem?? I use RO water but I do think that my filters and membrane need to be replaced. Those are on order and should be here any day. Anyone have any other suggestions? Has anyone ever used the Chem-Marin hair algae remover?

Also, what is everyone's opinion of syphoning the gravel during water changes? I have an aragonite substrate and I always syphon the detritus out of the gravel when I do the changes. I've noticed that since I did the large water change that when I syphon the gravel it has a really foul odor. I had never noticed that before I broke the tank down. Any thoughts????

Thanks for any help or suggestions you might have!!

[partobe]

Hpw often do you feed your fish and coral? You might be over feeding them. Your phosphates are probably high. I have a feeling once you cut back on your feedings and replace you ro filters things will turn around. I'm a new reefer so take my advise as such. I'm sure some of the more experienced reefers will give you more knowledgeable advise

[seaham358]

Test for phosphates, you need to add a DI housing on your RO unit to remove phosphates.
Its my understanding that the red slime remover kills bacteria (which cyno is) and some say it kills off good bacteria also.
This why some of us do not reccomend using any chemicals to try and correct a problem. These chemicals can create a new problem.
Syphoning is a good idea to remove trapped waste.

[SteveNichols]

I would get rid of the gravel. It is, simply put, a detritus trap. Getting all of the "stuff" out of it is nearly impossible. This makes it a great place to produce PO4 and NO3, the evil twins of algae production.

[Geoff]

how deep is your SB? foul smelling is not a great sign. it means you have some rotting going on in your SB. are you able to siphon out detritus over the entire SB surface? the important parts are deep under the LR.

it does sound like you have a SB full of phosphates.

be very carefull using those cyano away products. several are antibacterial (since cyano is a bacteria, not an aglae) and will kill off beneficial bacteria also. this can cause a tank to cycle again. it is better to let the cyano grow and siphon it all out during water changes. that way all of its bound nutrients are removed. if you kill it off than the nutrients that it has bound up will be rereleased back into the water column. this release into the water column will fuel other algae growth, hence your new green algae. if you siphon it out than nothing else can make use of these nutrients.

HTH,

G~

[seaham358]

Missed the foul smell in the post.. If it stinks like Geoff says its not good.
My SB broke down in my fuge and smelled like rotten eggs (sulfer) not a good thing. I would siphon out as much as possible and thing about changing the substrate out. I know its a lot of work but IMO having a bare bottom or a sand bed is much better then gravel or crushed coral.

[fishtank88]

ya the gravel/ crushed coral will trap stuff in the sand then you have to syphon it out all the time to get rid of all the stuff it traps
but with bare bottom no trapping problem, plus you can get your coral to attach and grow to the glass which will look rly cool

[cmccartt]

I feed my fish once a day. Is that too much?? Is a DI housing the only way to remove the phosphates? Will the RO membrane not remove them.

How would I go about changing to a sand bed in my tank? Could I simply remove the LR and siphon out the gravel and then add the sand? Would my fish be able to stay in the tank for this change. Also, does this mean the tank would have to re-cylcle?

Thanks for everyone's input!