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Dealing with my first algae bloom!

JayP

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I'll talk more about this in the coming weeks when I update my garden tank journal but wanted to get this out here.

Maybe I've been lucky up to this point, or maybe it's related to this being my first go at an inert substrate tank and new ferts, but as the title says, I'm dealing with my first algae bloom. I was already dealing with some spot algae on some of the plants and realized I might be driving the light a bit hard for a new tank with freshly rehomed plants getting used to the new conditions. I turned the par down a week ago to adjust. I also started out driving the CO2 rather hard until I just recently got it dialed down to around 30ppm which also occurred in the last week but the spot algae was already there before dialing it back.

I began noticing the water getting cloudier over the last few days which was a surprise since my other tanks were always crystal clear from the start. Even though this is a BDBS tank, I did run a short dark start while it cycled. It was short because I seeded the tank with other filter material and even had trays of cycled biomedia from other tanks. When I planted after a few weeks, parameters were good. Other than the lighting perhaps being too high, I also likely messed up by not being a little more aggressive on water changes early on. I just stuck to weekly 50-70 percent change like my other established tanks.

Some of the plants are still struggling to get established so I'm not too keen on doing a blackout. I'm considering investing in a UV sterilizer that I can set up as a temporary option on this and future tanks for just this issue. I'm kicking myself now for not taking advantage of some great marketplace deals on a couple used high-end sterilizers but that's life. So the question to the group, since I know some of you use them, what recommendations do you have for a reasonably priced sterilizer that's not too big but can get the job done on a tank of 50 to 75 gallons. I'm considering this unit: Aqua UV 15 watt advantage 2000 or perhaps the 8w version of it. I would likely set up a separate pump and pipes just for flow through the sterilizer ( although this unit hangs on the tank and therefore doesn't require out outlet pipe).
 
Save your money, don't get a UV sterilize. Clear water will come once the bacteria becomes robust. Why lower CO2? I'd increase it to 40+, more towards 50. An inert substrate must be run like one, extra everything. Keep EI level nutrients and just manually remove algae and increase water changes temporary. GSA is a clear sign of low PO4, I'd imagine the rest are similarly low. So, CO2 high, plenty of Nutrients and water changes to combat any algae. New tanks take some time to get the bacterial colony robust. It's that awkward period if you will. Lowering light can help, but too low can be an issue. Getting fast growth helps always on several levels. Healthy new tops can be planted algae free and plant mass is always a win.
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I've already changed this scape, but this get 50ppm CO2 and 27.2ppm NO3, 7.2ppm PO4 and 36ppm K a week with 50% changes. BDBS
 
I'm dosing @Burr740 macros and micros per instructions for the tank volume.

There are some fast growers in the tank and I want to try keeping them under better control than they were in my farm tank. A few of the usual suspects are already going nuts. I'll also be adding some fish at some point and so I wasn't wanting to push the CO2 too hard, although the fish in my other tanks haven't seemed to mind 40-50ppm, so I suppose I could tweak it back up a bit. Again though, the GSA was there when it was high.
 
I'm dosing @Burr740 macros and micros per instructions for the tank volume.

There are some fast growers in the tank and I want to try keeping them under better control than they were in my farm tank. A few of the usual suspects are already going nuts. I'll also be adding some fish at some point and so I wasn't wanting to push the CO2 too hard, although the fish in my other tanks haven't seemed to mind 40-50ppm, so I suppose I could tweak it back up a bit. Again though, the GSA was there when it was high.
GSA is never from proper levels of CO2. If the fish are fine, raise CO2 and keep it steady. Fast growing plants is a good temporary problem while things settle in. Per directions is a baseline, what's your end week NO3 (before the change)?
 

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