RainbowManatee
New Member
I've been fighting dinos on my sand surface of my 20ish gallon nano cube for about a month now with what seems to be limited improvement. I think I've always had dinos on the sand, but I thought they were diatoms, and they started blooming back in April after I got an RO/DI system and decided "I'm going to do more water changes and have cleaner water!" I didn't realize they were actually dinos (thinking the RO system wasn't removing silicates) until posting about it in May when my nutrients nearly bottomed out with NO3 at 0.9 mg/L and PO4 at 0.04 mg/L.
I started with a 3-day blackout in late May and my sand bed was CLEAR. Once I turned the lights back on, I decreased my light schedule to 6 hours with almost no whites in addition to decreasing the light intensity by ~1/3. I started dosing PO4 (NeoPhos) and feeding heavier to increase the nutrients. A week after the blackout, the dinos were back. I added two small UV sterilizers in the tank (this and this) and used a turkey baster to blow the sand nightly once the lights went out. The UV sterilizers also seem to have done little to improve the issues, but NO3 is now ~20 mg/L and PO4 has been ~0.12 mg/L. I started dosing silicates last week to try to get diatoms to outcompete the dinos by adding 1 mg/L of SpongExcel to the tank and removed the UV filters thinking it's probably best so the UV doesn't also kill any diatoms. I dosed 1 mg/L of SpongExcel again two nights ago and haven't seen much improvement in the sand bed and under the microscope it seems like there are no diatoms and all dinos (at least from the sample looked at).
My corals, especially my gonis, are pretty unhappy now for myriad reasons (reduced light, stopped feeding reef roids, probably depleted minor elements since I have done a water change).
How long should it take for the diatoms to take off? Any suggestions on what I might try now? Should I reintroduce UV? Try to seed with diatoms (somehow?)? I know water changes are not recommended, but I think it'll help my corals.
I feel like I've done all of the major steps without success: blackout, raise nutrients, UV, silcate dosing.
This is definitely killing any joy the aquarium was giving me.
Thanks.
Pic under 400x magnification
I started with a 3-day blackout in late May and my sand bed was CLEAR. Once I turned the lights back on, I decreased my light schedule to 6 hours with almost no whites in addition to decreasing the light intensity by ~1/3. I started dosing PO4 (NeoPhos) and feeding heavier to increase the nutrients. A week after the blackout, the dinos were back. I added two small UV sterilizers in the tank (this and this) and used a turkey baster to blow the sand nightly once the lights went out. The UV sterilizers also seem to have done little to improve the issues, but NO3 is now ~20 mg/L and PO4 has been ~0.12 mg/L. I started dosing silicates last week to try to get diatoms to outcompete the dinos by adding 1 mg/L of SpongExcel to the tank and removed the UV filters thinking it's probably best so the UV doesn't also kill any diatoms. I dosed 1 mg/L of SpongExcel again two nights ago and haven't seen much improvement in the sand bed and under the microscope it seems like there are no diatoms and all dinos (at least from the sample looked at).
My corals, especially my gonis, are pretty unhappy now for myriad reasons (reduced light, stopped feeding reef roids, probably depleted minor elements since I have done a water change).
How long should it take for the diatoms to take off? Any suggestions on what I might try now? Should I reintroduce UV? Try to seed with diatoms (somehow?)? I know water changes are not recommended, but I think it'll help my corals.
I feel like I've done all of the major steps without success: blackout, raise nutrients, UV, silcate dosing.
This is definitely killing any joy the aquarium was giving me.
Thanks.
Pic under 400x magnification
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