problem with surface algae

[anewbie]

In my 10ftx4ft aquarium - the surface has developed a layer of algae; what (if anything) should i do to resolve this issue.

 

I've not seen this before - the plants and area below the surface is fine and algae free but the surface has developed a layer of algae; i'm not sure if this is bad for the fishes (oxygen?) or why this algae is on the surface but with such a large aquarium i'm not sure if i should or can do anything about it...

 

@Seattle_Aquarist have you seen something like this before ?

 

[nabokovfan87]

Do you have a surface skimmer handy?  Especially on a tank that size, having an overflow or skimmer might be really helpful.

Edited November 30, 2023 by nabokovfan87

[jwcarlson]

I wouldn't say I'm "battling it" on a couple tanks.  But I have a couple that have this going on.  I don't really understand how or why.  It's basically like an algae slime.  I've tried netting it out or swirling a tweezers in there and balling it up.  It just comes back basically instantly.  I'm hoping it's a flow issue and when I get the new uplift tubes I can prevent it by directing some flow around the surface.

[anewbie]

On 11/30/2023 at 1:52 PM, nabokovfan87 said:

Do you have a surface skimmer handy?  Especially on a tank that size, having an overflow or skimmer might be really helpful.

Not a surface skimmer but the aquarium does have two overflows for the sump. The current is lacking on the surface even with nearly 800 gallon per hour turn over.

 

On 11/30/2023 at 2:05 PM, jwcarlson said:

I wouldn't say I'm "battling it" on a couple tanks.  But I have a couple that have this going on.  I don't really understand how or why.  It's basically like an algae slime.  I've tried netting it out or swirling a tweezers in there and balling it up.  It just comes back basically instantly.  I'm hoping it's a flow issue and when I get the new uplift tubes I can prevent it by directing some flow around the surface.

Do you know if it actually causes any problems - as i noted it is only on the surface and the cichild do spend quite a bit of time picking at it. Of course with the aquarium this size i can't really net it - i thought about adding several power heads to increase surface flow but not sure this is actually an issue.

[nabokovfan87]

On 11/30/2023 at 1:17 PM, anewbie said:

The current is lacking on the surface even with nearly 800 gallon per hour turn over.

Yeah. I agree.  It's like biofilm for the most part and maybe that stagnation is causing things to sit and build up and then end up with that algae/slime forming.

 

On 11/30/2023 at 1:17 PM, anewbie said:

Do you know if it actually causes any problems - as i noted it is only on the surface and the cichild do spend quite a bit of time picking at it.

It does hurt gas exchange.  Whether that matters given the sump oxygenation is tough to say without testing the levels.

[anewbie]

On 11/30/2023 at 5:09 PM, nabokovfan87 said:

Yeah. I agree.  It's like biofilm for the most part and maybe that stagnation is causing things to sit and build up and then end up with that algae/slime forming.

 

It does hurt gas exchange.  Whether that matters given the sump oxygenation is tough to say without testing the levels.

I don't have a way to measure oxygen level and even if i did i wouldn't know but i do have sponge filters in there so some air being injected. I'll try to find a power head in the basement - stuff sort of got thrown around when i moved a couple of months ago and if i can find it put it near the front and see if that shocks the stuff. The 450 is perfectly clear but the 550 has a film go figure. Maybe it is the loaches fault.

[nabokovfan87]

On 11/30/2023 at 3:17 PM, anewbie said:

I don't have a way to measure oxygen level and even if i did i wouldn't know but i do have sponge filters in there so some air being injected. I'll try to find a power head in the basement - stuff sort of got thrown around when i moved a couple of months ago and if i can find it put it near the front and see if that shocks the stuff. The 450 is perfectly clear but the 550 has a film go figure. Maybe it is the loaches fault.

That video when cory added the airstone to the pond might be relevant and maybe over time you can keep tabs on how his pond is changing / improving.  He basically has a setup where if he can get the junk off the bottom and moving it will do to the drains and he can clean it out.  If it doesn't circulate, then it just builds up (and has been before he was there).  The basic thing being that he has a really slow movement towards those cleanouts but it might be just enough circulation to keep things moving.  Maybe you can run a test with a time lapse camera setup and see if you're getting any sort of movement at all.  Then, adjust accordingly.

If it wasn't green, I would swear it was substrate related.

[jwcarlson]

My only affected aquariums are sub 55 gallons.  I haven't noticed an issue and everything has at least a sponge filter and the area around the place that bubbles up is always exchanging gas.  I don't worry about it, but it's annoying.

[Seattle_Aquarist]

Hi @anewbie,

WOW!  THAT IS ONE B-I-G TANK!!!  What is it about 950 gallons or so?

Algae is almost always caused by too much light (intensity, duration, or both) + too much nutrients.  You didn't indicate the water parameters, specifically nitrates (NO3) so I would start there.  With big fish comes big poop so in addition to fertilizer the amount of food and nitrogenous waste can cause high nitrate levels.

You would think that 800 GPH of filtration would be sufficient however for my tanks my filter GPH is about 10X the tank volume.  Extra flow in that tank would likely help.  I agree with @nabokovfan87 about a skimmer.  If it were my tank I would use an external overflow box with built-in skimmer, add some filter floss to the box and hook up a pump that will draw water from the tank, through the external overflow, and return to the tank.  You will likely have to change filter floss a few times a day until the surface clears.  Don't let a build up of the algae in the overflow box start to die, it will starve the tank of oxygen as it decomposes.  Also do not turn off the lights, the dying algae does the same thing.  Hope this helps! -Roy

Edited December 1, 2023 by Seattle_Aquarist

[anewbie]

On 11/30/2023 at 6:52 PM, Seattle_Aquarist said:

Hi @anewbie,

WOW!  THAT IS ONE B-I-G TANK!!!  What is it about 950 gallons or so?

Algae is almost always caused by too much light (intensity, duration, or both) + too much nutrients.  You didn't indicate the water parameters, specifically nitrates (NO3) so I would start there.  With big fish comes big poop so in addition to fertilizer the amount of food and nitrogenous waste can cause high nitrate levels.

You would think that 800 GPH of filtration would be sufficient however for my tanks my filter GPH is about 10X the tank volume.  Extra flow in that tank would likely help.  I agree with @nabokovfan87 about a skimmer.  If it were my tank I would use an external overflow box with built-in skimmer, add some filter floss to the box and hook up a pump that will draw water from the tank, through the external overflow, and return to the tank.  You will likely have to change filter floss a few times a day until the surface clears.  Don't let a build up of the algae in the overflow box start to die, it will starve the tank of oxygen as it decomposes.  Also do not turn off the lights, the dying algae does the same thing.  Hope this helps! -Roy

The aquarium is 10 feet long 4 feet wide and 2 feet high (~550 gallons); also i misquoted the turn over from the pumps it is approx 3000 to 4000 gph turnover.

(the pumps are 4 (FOUR) jebao dcp-5000 which are running at 80% capacity. I think each pump is rated at 24 gallon per minute so 4*24*60*0.8 or nomally 4608 gph then take off 15% for the lost energy moving the water up 3 1/2 - 4 feet or approx 3900 gph.

 

-

I'm not sure what you all are recommending the tank has 2 overflow boxes with intake  at water level - is this skimmer some other device i slip over the rim? will it go down far enough to reach the water (approx 1 inch from the edge of the rim). How will it interact with the current overflow boxes and the sump ?

 

Edited December 1, 2023 by anewbie

[Seattle_Aquarist]

Hi @anewbie  Not really, there are several designs out there but a external overflow box with a skimmer looks basically like this:


The trick is to get enough flow through the box to effectively draw the algae laden surface water into the box.  -Roy

[anewbie]

On 11/30/2023 at 7:13 PM, Seattle_Aquarist said:

Hi @anewbie  Not really, there are several designs out there but a external overflow box with a skimmer looks basically like this:


The trick is to get enough flow through the box to effectively draw the algae laden surface water into the box.  -Roy

I think what you all are suggesting might be the trick but not practical on an aquarium like this - first the flow would have to be quite higher than the current flow and sending all that water down to the sump would require massive amount of tubing and days of planning. If the box shoots is self contained and shoots the water back out into the aquarium and doesn't have to be routed - i would still need 4000 to 8000 gph flow i think since the current 4000 gph isn't sucking in the algae fast enough to digest it.

 

Or did i miss something - also i did turn on the uv system the last weekend but it doesn't seem to be helping - basically all the water is now flowing through a 40 watt uv thingy. Maybe the actual algae isn't being sucked into the sump - maybe somehow it is bringing in water just below the algae or something like that - no clue.

--

I'll measure the nitrate level this weekend and then respond back to this thread - what happens if i turn off the light for 2 weeks? The water has a 3 gallon per hour drip system with ro water so i kind of suspect low nitrate but will double check - the largest fish is a clown loach around 6 inches - while there are a lot of fishes in there it is only marginally more than i had in my 120 in an aquarium that is 4 1/2 times larger.

--

Lights are off now but either tomorrow or saturday i'll take pictures of the current overflow boxes and where they collect water to help move this along.

 

Edited December 1, 2023 by anewbie

[nabokovfan87]

@anewbie basically what I was talking about is a weir.  I'll try to grab a photo. Overflow box being a design on that same theme. Grates, which allows water to drop a few inches and are wide enough to allow a good amount of surface clearance. You may already have those in the setup, but it's just one of those things where the diameter of the drain could be causing some weirdness. I'm not quite sure.

The grates keep the fish out, allow water to flow through, but the standpipe in that section has the waterline lower than the grate and that just allows the surface to be cleared.

Overflow box means that you just don't have to drill a tank, but the concept is the same.

 

[anewbie]

The nitrate measured between 0 and 5 using liquid test; while it is a new kit all of my aquariums 'cept maybe the guppy tank should have near 0 nitrate so i just have to assume i did the test correctly 😉 I might get some strips at petco to cross test when i go by this afternoon:

@Seattle_Aquarist @nabokovfan87 this is a picture of the current overflow and I would think it does the skimming you mentioned but if not can you explain how it differs from a skimmer (there are 4 of these connected to two overflow boxes):

[Seattle_Aquarist]

Hi @anewbie

That is indeed a skimmer but with the slots horizontal as detritus (aka floating algae) builds up around the edges it becomes less effective, that is why one with vertical slots should do a better job.  How many gallons are flowing down that horizontal skimmer per hour?  I suspect it is one or two pumps worth maximum.  Do you use a 'splitter' where just a fraction of the water returns through the skimmer and the rest through the bulkhead? -Roy
 

[anewbie]

On 12/1/2023 at 11:59 AM, Seattle_Aquarist said:

Hi @anewbie

That is indeed a skimmer but with the slots horizontal as detritus (aka floating algae) builds up around the edges it becomes less effective, that is why one with vertical slots should do a better job.  How many gallons are flowing down that horizontal skimmer per hour?  I suspect it is one or two pumps worth maximum.  Do you use a 'splitter' where just a fraction of the water returns through the skimmer and the rest through the bulkhead? -Roy
 

Approx 1000 gallon per hour as there are 4 of them and the total flow is whatever i posted above. There a slits in the side and most of the water is 1/4 an inch below the surface. I did add a aqueon powerhead this morning; it reaches about 1/2 across the tank but the clip is too thick for the frame - i ordered 2 stronger power head on amazon that have suction cups and they will arrive this weekend and i'll see if that solves the issue - they are super cheap $15 each; and less problematic than trying to do something with the sump if they fix the issue - i want to try them before getting 2 more to make sure they make surface waves - the tank is 4 feet wide so it will probably take 4 - the festum and angels do spend a lot of time eating that gunk at the top but hopefully i can kill it off - dead dead dead.

[nabokovfan87]

@anewbie Can you take a video of the skimmers doing their thing?  I'd be interested to see the flow characteristics.

[nabokovfan87]

On 12/1/2023 at 9:59 AM, Seattle_Aquarist said:

That is indeed a skimmer but with the slots horizontal as detritus (aka floating algae) builds up around the edges it becomes less effective, that is why one with vertical slots should do a better job.

It should have both slots from what I can see in the photos. On the right side you can see some of the vertical ones, but they do appear clogged.

[anewbie]

On 12/1/2023 at 2:53 PM, nabokovfan87 said:

It should have both slots from what I can see in the photos. On the right side you can see some of the vertical ones, but they do appear clogged.

they aren't clogged; they look clogged but if they were clogged all the water in the sump would be pumped into the tank; a video woudln't help much because all you see is water trickling in - the slots are on both sides and the front; if they were totally clogged the water would raise above the top and flow in over the top but as you can see the top is not covered; but the water strains in through the slots on the side leaving the slime in the tank - i think the power heads will do the trick and when i get one with suction cups i will set them up and see if that solve the issue. The relatively weak aqueon 50 i put on there actually did a pretty good job but since the clip wouldn't get over the rim i removed it so i could close the lid after a few hours.

[anewbie]

What a pair of strong power thingy do:

 

[anewbie]

I now have 4 very strong power heads running (those thing are cheap); and up to around 2000 gph of surface agitation:

 

Not total success but definitely thinning out; if it doesn't clear in another weak i'll another power head to make a cross current in front. Poor angels have to hide behind the power heads but everyone else loves the current 😉

 

[JoeQ]

Almost recommended these before reading the post.

https://www.amazon.com/Aquatop-Skmr-Surface-Intrnl-65Gph/dp/B07K2LXNXD?pd_rd_w=QdJLh&content-id=amzn1.sym.300a3262-566c-4179-a45e-2e093bbf316d&pf_rd_p=300a3262-566c-4179-a45e-2e093bbf316d&pf_rd_r=963W5WP8SKA3SXRTHB90&pd_rd_wg=P9vaG&pd_rd_r=bd0d4733-e3f7-4a5f-ba4a-f20f800ab084&pd_rd_i=B07K2LXNXD&psc=1&ref_=pd_bap_m_grid_dv_rp_0_14_i

Image my embarrassed if I had! 😬😳🤣

[anewbie]

I should take another picture - maybe tomorrow or the next day - overnight 80% of the algae broke down into basically nothingness - this current thing seems to make it feel uncomfortable in its skin - sort of like when you put salt on a slug.

 

The angelfishes are not too happy with it; but at least 'their' corner is current free so they have a place to retreat when not eating. They are such a lovely pair i should move them to another aquarium and let them breed without nasty festum eating their eggs.

 

Edited December 12, 2023 by anewbie

[anewbie]

And here is another picture - still some particle but most of the actual algae is gone:

[anewbie]

Well the problem is completely gone and the top is a mirror once again; i guess the solution was a little motion on the surface; of course it cost $65 for those power heads; i'll probably leave two running for a while - well one more week then remove them all. I should add one of those thing (what do you call them) that makes current near the bottom for my L206; they love current (I have 4 to 6 of them in the aquarium). They seem to get along much better with loaches than the bn and i don't really understand the dynamics - maybe they are a little larger or a little darker 😉 Or maybe the loaches are plotting against them only time will tell.

 

Anyway this is my final post to this thread since the problem has been resolved; for a small tank a small power head would have resolved it - just noting in case 2 centuries from now someone stumble upon the same issue.