Here are some photos of my tank, which I have deliberately let go for about two weeks just to see what would happen:
Chronic Blue-Green Algae
- Thread starter tackful
- Start date
Yeah, that's a bad case of BGA. I think it's probably over fertilizing and too much light. Are you able to remove the driftwood, scrub them clean and treat them for an extended time with E.M. outside the tank. And suck out as much of the GBA in the tank as possible? With no fert and reduced light and/or photo period, you probably don't need injected CO2.
Byron Amazonas
AC Members
Yes, will do right away. Just finished an 80% water change and was able to vacuum up all the BGA on the substrate, which was good. Now I'll take care of the driftwood, reduce the photoperiod and treat everything with EM (and no ferts or co2, either!).
What kind of filtration are you using, any dead spots with low flow? That's where I've seen BGA take hold first every time I've gotten it. That and an hour or 2 of strong window light, west or south exposure being worse, no matter how far away from the tank.
I have a 20-40gal canister filter, the outflow of which I can redirect to the front center of the tank, which is probably a bit of a dead spot and has always been the worst area of BGA. Most of the year there is strong indirect sunlight from the west facing windows, which are about 15 ft away and provide such a good view that keeping the shades down in favor of the tank would be unreasonable. Unfortunately moving the tank is also not an option, so I'll just have to hope that redirecting the filter outflow might be the missing answer.
Certainly I am proceeding with the EM and driftwood scrubbing as suggested, but it's also something I've done in the past, along with the total tank emptying and cleaning of a few months ago, so I really hope that more vigorous waterflow across the substrate will make a significant difference. Thanks for the help and interest.
One of the conditions that can trigger an outbreak is having your Nitrogen levels reach 0. This algae can do atmospheric Nitrogen fixation if no other sources are available. The frustrating part is that once it starts a colony not fertilizing doesn't hurt it and fertilizing only makes it grow. I dealt with it in my tank way back when with a couple 3 day blackouts (a couple because the first one didn't kill it all). The blackouts have to be complete though to work, I wrapped my tank in black plastic to shut out all light. Plants have enough reserves to survive, but the algae doesn't.
0 nitrogen is a blue green algae advantage situation.
Just a hunch though, what is your water source hardness kh and gh? I have a feeling you generally have enough macros N P K, but you might be lacking sufficient Calcium and Magnesium for good plant growth. Do you have any snails in your tank? What do their shells look like? If they have etching white ends that would be another clue that the Ca and Mg are lacking. Keep in mind that plants need about 1-1 Ca-K and 4-1 Ca-Mg ratios. So if you dose 20 ppm K you'd want at least 20 ppm Calcium and 5 ppm Magnesium.
0 nitrogen is a blue green algae advantage situation.
Just a hunch though, what is your water source hardness kh and gh? I have a feeling you generally have enough macros N P K, but you might be lacking sufficient Calcium and Magnesium for good plant growth. Do you have any snails in your tank? What do their shells look like? If they have etching white ends that would be another clue that the Ca and Mg are lacking. Keep in mind that plants need about 1-1 Ca-K and 4-1 Ca-Mg ratios. So if you dose 20 ppm K you'd want at least 20 ppm Calcium and 5 ppm Magnesium.
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I saw BGA most often with low flow, low-no nitrate, tall stem plants & window light. My tank at that time had more plants than your pic but not what I'd call more than medium planted at most (except for hopeful newbs, lol). I'd increase flow, trim plants & add KNO3 (stump remover) once in a while if N was less than 10 or 20ppm. Neglect those & BGA would come storming back. Now I have high windows that I'm unwilling to block & a gift tank & fish that came with BGA. After a round of erythromycin to kill it once, I've resorted to dosing Excel every week or 2...way less often than Seachem says, but it seems to be working for the last several months.
SnakeIce: Thanks for your reply, sorry for my late response. Kh/Gh is 3/4 respectively, and Ca is less than 1. Mh is 30, and Mg is 7. I use the Nutrafin Ca test kit, and if I've done my math correctly, which I believe I have (it gets a bit complicated when deriving Mg and Mh from Ca) then my Ca-Mg ratio is way of of whack. The snails seem to be grey and streaked all over. I hope they are not reacting to the hydrogen peroxide which I have used in place of EM at 1ml/gal.
I hadn't known that adding N once BGA has begun only helps it. Thanks for that.
fishorama: Interesting idea about the Excel. Simple and relatively inexpensive. Thanks.
I hadn't known that adding N once BGA has begun only helps it. Thanks for that.
fishorama: Interesting idea about the Excel. Simple and relatively inexpensive. Thanks.
