Cyano Assistance Needed

Daniel C.

Reefing newb

I am a novice I have a 75 gallon tank that has been up for about four months. I am having a Cyano issue. For fish I currently have, 3 chromies, 3 fire fish, 1 scooter blenny, 1 diamond goby, 1 chocolate chip starfish, 1 sally lightfoot crab, and 1 clownfish. I went to my local fish place and my water results were as follows: Ammonia - .75, Nitrites - 0, PH - 7.4, Nitrates - 15, Phosphates - 0. I currently have a protein skimmer that is rated for a 110 gallon tank as a HOB as well as a filter with active charcoal and PVC substrate rated for a 110 gallon tank. I have two power heads, one in the back going down the length of the tank and one on the opposite side front corner pointed up. I am having an algae issue especially with Cyano and I need help. I have attached a pic of the current tank. Any assistance is greatly appreciated.

Thank you,
Daniel C.


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Are you still having this problem? If so here is how I cured the same problem in my tank. I would recommend doing as many of these steps as possible

1. water changes of 15 to 20% *WEEKLY*
2. adjust your skimmer so that the skimmer cup fills at least half way up every 2 to 3 days. (it may be very important to maintain a constant water level with an auto-topoff system). also don't make a change to skimmer cup positioning more than once every 12 or 24 hours. keep adjusting until you figure out the right spot to get the skimmer filling the cup at least 1/2 way up every 2 to 3 days. one setting might seem like it is wrong because the cup fills up, or doesn't fill up, but give it a day just to make sure. Once you find the setting, leave it there. if it happens to fill up too fast once or twice after it seems like you already found the right setting it may just be a fluke and stick with the setting for a few days before adjusting again. (this is my experience with my in sump skimmer)
3. more flow. I bought an icecap gyre 2k I think and it works great in my 90 gallon (you can skip this step to save money)
4. chemiclean by boyd industries cyano remover. follow the directions. if that doesn't work, then after 2 or 3 weeks (and 2 or 3 water changes) try again, but do the recommended amount *each day* for 3 days so that after 3 days you have 3x the recommended amount in the tank. wait a day after the last treatment and do a 30% water change and throw in a bag of carbon into the system. leave the bag in for a week. remove the bag, do another 30% water change. maybe by now you can turn the skimmer back on. if it still overflows like crazy even after adjustment wait a few more water changes before turning the skimmer back on. It sounds crazy but step 4 was the final nail in the coffin for my cyano problem.

Once your problem is fixed I think your tank will be much happier with 15 to 20% weekly water changes for as long as you have the tank.