My live rock is dying off?

Question

i have 2 48" flourecent lights, wet dry filter that cycles the tank 15 times an hour, im doing 10% water changes every two weeks, water temp is at 80. what am i doing wrong? i just ordered a bottle of purple up, will that help?

Answer 1

No. Also, 10% every two weeks?

honestly if you knew what grows on and lives in live rock, you would never use it to cycle your tank. Your tank is cycling. It ISN"T like fresh water. Placing live rock in a new salt tank pretty much kills a lot of creature and animals in and on it due to ammonia spikes. People who use live rock pretty much kill most of what is on it yet there are some things that survive. Your tank is cycling. Bacteria dieing and feeding. this will continue for a period of time. Water temps should be a bit higher. Where is your PH sitting at? 8 or better?

10% water changes right now are not enough. You have a new tank. 25% once a week is where you need to be. This will help to remove nitrites and ammonia build up and relieve stress on your rock. Also, how much rock did you dump in your tank at one time and how large is your tank? For a saltwater tank, live rock should be added at 15% of the tank volume per every two weeks until you get to where you need to be. Tanks larger than 50 gallon or reef tanks should have a DEAD rock base to start with live rock added later. Rock, plants, fish, invers makes no difference to the biofilter. they all play their rolls and need to be added accordingly.

Just as when you are ready for fish. Tanks less than 6 months old one inch of fish per 5 gallons every 3-4 weeks. NO MORE. you can double that amount after 6 months. At a year, add what you want but no more than 1 fish (plant invert) per week.

Salt water is not to be rushed which is why many fish keepers prefer fresh water. They are not the same. PATIENCE here.

If I can help further, feel free to email me.

Answer 2

Die off on live rock during a cycle is completely normal. If your are doing water changes during your tanks cycling period all you will do is end up extending the cycle time. Let the ammonia spike then the nitrites then the nitrates will come up. After ammonia and nitrates are back down to 0 and your nitrates are up then start doing weekly water changes. 10% every 2 weeks isn't enough for a new saltwater tank. 10% every week is fine as long as your nitrates are staying down. If your nitrates are going up above 40 then do more of a water change. If they are less than 10 your perfect.

Don't use the purple up stuff. When your tank is cycled and everything stabalized the corraline will start to grow. It takes some time but it will happen.

80 degres is fine for a normal tropical saltwater tank. 78-80F is great unless you are getting into raising some region specific species. Most of your average saltwater fish and inverts do well in this range. Running higher temperatures does have some advantages but also creates more problems. When you get more experienced at controlling wastes, algae, and oxygen in the tank you can run it a few degrees higher but until you research all of this 78-80 is a great place to start.

Your main problem I think is time. It's never on our side for saltwater. The rock turns white and dies off before it rejuvinates itself and begins growing again. You can cycle your tank with many things and over the counter products but I still find live rock to be a great way to cycle and establish a tank.

Answer 3

I also agree that the water changes aren't enough. All the purple up contains is calcium carbonate and iodine - you'll add this by doing water changes, because the same ingredients are in the salt mix.

Here are some things to look for as far as why the coraline algae is dying

pH - this should be between 8.2-8.4

salinity - should be between 1.020-1.026 for fish, 1.023-1.026 if you have invertebrates (snails, shrimp, crabs, corals, etc.

lighting - Your lighting is probably on the low end of intensity for a saltwater tank, even with two tubes. Also the color temperature (K value) and wavelengths (measured in namometers) will make a difference in how well the algae can produce food (photosynthesis). The bulbs that come with the light fixtures don't cut it for having the proper wavelengths - you'll need something that produces more light in the wavelengths that plants can use around 680-700 nanometers, although some light from 400-700 nm will be used. Check the packaging to be sure the tubes you choose have these wavelengths. A 5,500K is closest to actual sunlight, 6,500K is also good, and compact fluorescents use around 10,000K - closer to sunlight underwater and better for inverts. The higher the number, the "whiter" the light will appear. Since your fixture has two lights, you could choose two of the same, or mix them.

Your filtration and temperature shouldn't be a problem, but you shouldn't let the tank get much over 80o - if anything turn the heater down a few degrees to 76-78.