algae question

[MarkLW]

we have a 120 gallon reef tank with a 3-4 inch deep sand bed. We have had it for about 3+ years now and over the past few months we are having really bad algae issues. We have hair algae growing over large portions of rock along with cyno and also a very strange dark green almost black looking velvety algae growing on one side of the tank sand bed. It appears our water levels are all looking alright but we cant figure out why now all of a sudden we are being plagued with all these diff types of algaes. We currently only have 3 penguins on the tank and a magnum 350. 180 pounds of rock and probably the same or more in sand. lots of softies and one little nemo running around;) Any ideas how we can get our tank back? Also does anyone know of a really good magnet to clean the glass with for 1/2 inch glass the little magfloats just dont seem to do the job.

[erikharrison]

How old are those lights? Have you checked for phosphates? What's your stock list? Are you keeping up with the tank's water changes or has there been neglect? Are you using tap or RO/DI? Is your TDS meter (if RO/DI) functioning properly? If I had to guess at this point, I would say phosphates and/or lighting, quite possibly both.
20% water changes for the rest of the week, and buy a phosphate test kit if you do not already have one. Test, test, test, and test again.

When you really sit down and look at algae problems, it usually stems from two places, water quality and lighting.

[RayAllen]

Erik made a lot of good points. It also sounds as if you do not have enough flow in the tank. When algae is growing on the sandbed it usually helps to get flow over it. 2 Hydor 4's would be great assuming your tank is either 4 or 5ft long..

[Ping]

A 3-4 inch sandbed can also be a source of high unprocessed nutrients. You may want to really stir the sandbed up and then replace the filter pads. I would do this a couple times.

A sandbed should have a depth of over 4 inches or 1 inch or less, with preferably Sugar fine sand. Also you do not have enough current to maintain a deep sand bed (DSB).

In your situation, one solution would be to remove much of the sand, and conduct numerous water changes. Removing the sand will make a mess.

This would be one way to help with long term excessive nutrients. However it will not kill the algea immediatly these things take time.

I would look at increasing the current and your cleanup crew.

[MarkLW]

thank you all! those are all great suggestions. Think i'm going to probably have to do all of them. think i may try the sand stirring first before i actually remove any sand cause there is so much rock on it and we really dont have a very good filtration system going yet. we had dan build us a wonderful sump and fuge but my husband has not had a chance to hook them up quite yet.. trying to get this under control before our new arrival comes this march, lol.. not sure how old the lights are but know we replaced them a while ago off of e-bay. know we did get the cheaper ones (we have the geiseman 250 long light, one on each end and moon in the middle) i will see if i have a phosphate test somewhere. we use RO/DI water and you are right about the water changes. usually go quite a long time without them but i will try to gett all teh water changed this month. hopefully that will help also. will run all this by my husband and see what all we can do! thanks again, been out of the loop for quite a while.

[Fish4life]

be careful when messing with the sand bed. It is possible to release gue from dead spots in your bed into your tank, which could potentially kill everything!

[MarkLW]

we have penguin 1140's, 300 gallons per hour 3 of them.. is that enough flow?

[erikharrison]

I have 3600 gph in my 75. 2400 would be GREAT. 2400= two Hydor Koralia #4s. They are inexpensive powerheads and everyone seems to really like them. You can find them at most of our sponsor's stores.

[Ping]

be careful when messing with the sand bed. It is possible to release gue from dead spots in your bed into your tank, which could potentially kill everything!

Do you have a reference of this actually happening?