[ahem]

I have a thriving tank I setup in September. Everything grows well, inhabitants are happy. I have not had one algae incident yet except near daily GSA. I have been gradually boosting my concentration of phosphates to over 3ppm and hardly put any nitrates in (which usually range from 10ppm to 30ppm+, hard to tell exactly on the API test). I've read GSA can be the result of too low phosphates or "phosphates out of balance with nitrates" (which is not a very helpful statement). None of phosphate/nitrate movements I've made have abated the GSA in anyway, it always comes back although strangely there are some days it seems to not grow.

I am very overstocked with Endlers, is there is an organic waste component to GSA? I manage that with extreme plant density, modest feedings, 10% daily water changes, and I use liberal amounts of both Seachem Stability and Seachem Pristine bacteria supplements to break down wastes. I also avoid putting in much nitrate (currently) due to overstock. The shrimp population is exploding so I am assuming my water quality is pretty good.

The tank also gets a little light from outside (its near a sliding glass door), could that be the issue? There is no way I can change that so I'll have to work around it somehow.

Here it is April 1 a few days after thorough glass/tank cleaning. You can see the GSA already forming.

Then here it is just 4 days later, time to scrape! And this is definitely GSA and not GDA because it is a workout getting it scrapped off. Though interesting enough, I notice both RCS and pond snails like it when it is fresh, normally I don't think they like GSA because it's too hard. It's an acrylic tank so I have to use a nylon scrubby vs a metal scraper. I'm going to try one of those magnetic scrapper. But how do I stop this???? I'm about to move from Seachem liquid ferts to NilocG dry ferts in a PPS mode. I'm hoping this might balance things out a little but it seems a shot in the dark.

 

[Deanna]

Yes; there can be an organics-problem component to any algae. For the sake of your sanity and, perhaps, to minimize instability (which is bad for plants), I would probably not do daily water changes unless there was a crisis, and then only to a specific objective of removing a certain percentage of water more gently than all at once. Make your life easy and do 50% weekly. I also don’t think that you need those products to “breakdown” waste. Purigen may be a better alternative in order to absorb some of these organics.

Direct sunlight could be a problem, but not just ambient light.

As far as recommended levels of PO4, and I’m assuming this is a high tech rank, I would target a minimum 5ppm level of PO4 or 10% of the NO3, whichever is greatest, to see if that helps with the GSA.

I think we could get more members commenting if you provide as much of the following as possible (excuse any information that you may already have provided):

• How long has the tank been setup?
• Light (make & model): ideally, PAR and PUR reading at the substrate and photoperiod?
• CO2 setup (if any) and, if you inject CO2 (pressurized or DIY?), what is the CO2 ppm level, how is it measured and how is it timed with your photoperiod?
• Current NO3, PO4, GH, KH, pH and TDS readings and which test kits/devices are used for each?
• What you are dosing (product and quantity), in terms of ppm, and how often?
• Substrate type and how long has it been in place?
• What is your filter setup?
• Cleaning regimen (filter and water change frequency and amount)?
• Circulation: surface rippling and are all plants gently moving from top to bottom?
• What is your water source and do you use a water softener?
• What is your tank size?

 

[ahem]

Thank you for the response!

Make your life easy and do 50% weekly. I also don’t think that you need those products to “breakdown” waste. Purigen may be a better alternative in order to absorb some of these organics.

Not really possible for me. I have a tank of shrimp and I notice far less of them for a few days after any water change > 20%. I think it forces them to a molt. It's a 50G so taking a daily 5G bucket full is actually rather quick, easy, and simple. I do 15-20% of a water change at trim time every other week, doing the squirt into the gravel/siphon trick to get anything. Actually with all the shrimp and pond snails, the tank usually has little to no mulm build up. Occasionally if I have been over feeding I will see this (one of the things I look for).

As far as recommended levels of PO4, and I’m assuming this is a high tech rank, I would target a minimum 5ppm level of PO4 or 10% of the NO3, whichever is greatest, to see if that helps with the GSA.

5ppm is double the PO4 where I am now. So I will move it even higher.

• How long has the tank been setup? 7 months
• Light (make & model): ideally, PAR and PUR reading at the substrate and photoperiod? I don't have any of those readings, it's 18 to 20 inches to the substrate and I use (2) Fluval LED 3.0 lights with a very gradual and tapered "normal day simulation" with a mid day "overcast". My max illumination from both lights hits about 90% but only for the early and late peaks (I use 90% as a point, not a sustained line. Higher I start to get lots of pearling, which I know if supposedly good, but also GDA and ridiculous growth where I have to trim weekly or even more often. I would not raise light at this point. And yes, I think I am just inside "high tech". I make it a long day as I like to view the tank. Non moon lights on gradually from around 6am to around 930pm. Again very tapered so there is a long "late evening" (mainly for viewing).
• CO2 setup (if any) and, if you inject CO2 (pressurized or DIY?), what is the CO2 ppm level, how is it measured and how is it timed with your photoperiod? I gave up measuring bubbles since my needle value is not reliable and instead use a Milwaukee pH controller. I have it set for a drop to pH 6.3 before shutting off. Nominal is pH 7.2. I'm satisfied with this level as well. I need not risk my inhabitants with more CO2 and growth is too fast, if anything. It's starts an hour before lights on and stops an hour before lights out. It's a CO2 tank not DIY.
• Current NO3, PO4, GH, KH, pH and TDS readings and which test kits/devices are used for each?
  • NO3 ranges 20-30+ PPM hard to tell with API. I have several different cheapo NO3 kits and they all are poor.
  • PO4 ~ 2.2ppm currently measured with a Hanna PO4 checker which is very reliable.
  • GH ~ 11, KH ~6 (both are roughly a little higher than tap which I use).
  • pH 7.2 nominal, 6.3 at my max CO2.
  • TDS is typically ~ 300ppm.
• What you are dosing (product and quantity), in terms of ppm, and how often? Seachem everything daily. Daily doses of seachem:
  • 20ml PO4 (~ .6ppm)
  • ~1ml NO3 average (~.3ppm again huge bioload supplies a lot)
  • 5ml Potassium (~ 1.5ppm)
  • 5ml Iron (~.1 ppm)
  • 5ml Trace
  • 5ml Excel
  • 10ml Stability
  • 10ml Pristine
  • 5ml Advance
  • once a week I substitute 5ml Flourish for the Iron and Trace).
  • 
    
  • Converting tonight to NILOCG dry (although I wonder if that is hasty). I'm going to try PPS daily but probably with attenuated NO3 due the fish load.
• Substrate type and how long has it been in place? Flourish Black Sand since the beginning
• What is your filter setup? Dual Aqueon 200GPH cannisters, loads of bio material inside.
• Cleaning regimen (filter and water change frequency and amount)? every other week trim with a ~20% change, daily 10% change (again to keep my shrimp from molting). Filters cleaned as needed. Substrate cleaned where I can get to it. Algae scrapped > 1x weekly.
• Circulation: surface rippling and are all plants gently moving from top to bottom? There is some movement but plants are very dense. I have a tangled dense "hedge" of stem plants across the back that would lift out in one piece. I run a sinking air hose across the whole bottom back connected to a powerful air pump and when CO2 is out and for a few 15 min periods through the day when it is on, it bubbles vigorously in the back which gives me good circulation in the low flow area. I have one power head up top to assist. Cannisters have one spray bar I had to attenuate through a sponge or it pushed the fish everywhere. The other cannister runs through a HOB-like "polishing unit". Surface has some minor agitation. In 7 months I have had NO algae between plants or anywhere else. Only normal early GDA which went away. I have only had GSA on the glass and on slow grower plants like anubias and java fern. I do not believe I need more water movement.
• What is your water source and do you use a water softener? Tap. Hard-ish water. No softener. I believe in working with what you have and not messing with it. As you can see from the above, I already have quite a regimen.
• What is your tank size? 50G

I appreciate your response. The 5ppm phosphates is something I'm going to try, I thought I was already pushing it at 2+ppm. I'm not sure adding to this will get me any more responses, the site has been very subdued, I see many other people with NO responses. I know someone can't tweak my tank because what works for one person's tank probably won't work for another. I'm hoping there is someone who might know something about GSA, maybe they had a battle with it they conquered. If there are other sites where you can get more readily advice, please anyone chime in.

 

[Deanna]

Your description indicates a, basically, well-kept tank. Everything I’m about to suggest is designed to give you ideas for possible improvements that may reduce your GSA, although GSA does tend to develop, in spite of our best efforts, on slow-growing plants and hard surfaces.

Light looks ok, although the photoperiod is on the long side. As one of the possible solutions, you might try to give a 4-hour lights-out period in your “overcast” area, rather than having any light during that time.

CO2 looks ok, but most of us would shoot for a 1-1.5 pH drop (watching inhabitants for stress while gradually doing this). Shrimp can handle lower pH and pH swings from CO2 don’t affect livestock, since there is no TDS involvement. However, your tolerance limits for maintenance are legitimate and you will have to decide about that.

Cleaning: I clean my filter at least twice a month as one aspect of minimizing organic build-up. Keep your bio-media, of course, but don’t worry about any effect upon BB due to frequent cleaning. Any concerns about that should be alleviated when considering that it almost instantly recovers to meet demand and that there is plentiful BB in your tank, as well as plants to take care of, even compete with BB, most organics. Although adding lots of bio-media won’t generally hurt, it’s not necessary to use more than recommended in a well-planted tank. Deep vacuuming of the substrate in a well-planted tank, such as yours, is not necessary. Just do a light surface vacuuming if you think it’s needed.

Your description of your bio-load leaves me thinking that it may be high - you’ll have to judge that - so it is possible that organics are high. Your NO3 reading of up to 30ppm and only adding .3ppm daily along with 10% daily w/c’s certainly indicates this. I’d add Purigen to help reduce the organic source.

If you haven’t done so, use RotalaButterfly
to get an idea of your nutrient accumulation, which may indicate anywhere from too little dosing to too much dosing. The “Nutrient Dosing Calculator” will tell you how much your ferts add and the “Nutrient Accumulation Calculator” will help you estimate if your dosing is where you want it to be in view of your w/c’s. A TDS meter would help you understand how your dosing (which includes food) might be when you compare it to your tap water, e.g.; if TDS is significantly higher in your tank than your tap, overdosing of something may be occurring and, as important, the opposite might be occurring. Armed with that info, you can either adjust dosing or w/c’s, or both.

The circulation question is more about ensuring that nutrients are being delivered uniformly and not about directly affecting algae. As long as you are comfortable that good mixing is occurring, then that potential issue is addressed.

 

[ahem]

Lots of good stuff Deanna, thank you! I was not knowledgeable of RotalaButterfly and it looks like a lot fun. Going to give that a whirl.

My key takeaway from your comments, I'll focus the next step on making sure the water is clean. Maybe it already is but this will make sure. I do let the filters go a while, occasionally to the point flow slows and I have to clean them. I've been relying on biological control with lots of biomedia, plants, snails, shrimp, and adding BB daily with 10ML each of Seachem Stability (nitrification) and Pristine (waste break down). Those BB supps are probably OCD overkill, but I like the peace of mind and they don't cost that much. Hopefully they aren't what causes the GSA problem! But even with all that I have wondered if there is still a lot of problematic organics in the water column. I would guess I have as many as 200 endlers and as many shrimp (I know, time to donate). They are of all sizes of course, tiny fry to adults. But I put a lot of food in there to keep them fed.

So I'm going to try every other week filter cleaning, which is a lot more frequent for me. I won't obsess about harming the BB. I'll also try Purigen and check out your suggested RotalaButterfly + TDS technique to determine solids. I have rotated activated carbon in the filters at times, I'll have to read up on the differences with Purigen.

Lights might need to go down, and your afternoon lights out idea is a good one since my viewing is mostly in the evening. But I'll save that one for next depending on the mileage I get from my "water improvement plan". I have just switched to dry ferts (NILOCG) last night so that's probably enough changes for now.

Really appreciate the help!!!

 

[Plinkploop]

Sometimes you can have too much bb. I recently experienced this- made my water cloudy and caused a film. I cut back using it and kept up with changes and it cleared. Not 100% convinced it was only the bb causing it but I'm 100% it contributed.