surface slime ... baffled !!

[hamfist]

Not quite sure which section to post this in - mods please move if inappropriate here.

My 80 gallon tank has a surface slime problem that I just can't seem to get to the bottom (top ?) of.

The tank is mature, has only one small 4" flowerhorn in it, and is filtered by two externals (one is a 1400 lph, other is 650 plh ... that makes a turnover of about 7x per hour).
Lighting (one 29W bulb) is on for two hours per day. There is no natural sunlight on the tank.

I am getting a clear/ very light brown slime covering the surface. It needs clearing every couple of days.

Everyone's first thoughts will be to increase surface movement but I have a ton of surface movement. As well as one of the externals emptying into the tank via a spray bar right at the surface, I have a 2400lph wavemaker aiming right at the surface to get as much surface movement as possible. There is way more surface movement than in any other tank I have ever had, yet have never had this problem before.
I do weekly 30-40% water changes. Just not sure what else I can do to combat this stuff.
My water stats are zero ammonia and nitrite, and nitrates are around 15-20 ppm. Temp is 26 celcius.
Substrate is gravel. Decor is two granite rocks and plastic plants.

Any thoughts/advice ?

 

[ar0wan]

#1 it's just protein
#2 it's not hurting anything
#3 HERE is how to deal with it

 

[hamfist]

#1 it's just protein
#2 it's not hurting anything
#3 HERE is how to deal with it

1/OK, as I suspected.

2/ Yes, it is hurting my aesthetic enjoyment of my tank.

3/ Cool, thanks. the Fluval skimmer does not seem to be widely available in the UK, but there is a reasonably priced Eheim one that is. I shall get one !

It still puzzles me though. An 80 gallon tank, with one small fish in it. Ok, I feed 3-4 times a day, but it really isn't that much protein going into the tank. I'm really surprised that the filters can't cope with it.

 

[hamfist]

Any other opinions really appreciated !

 

[rhodes_96]

1/OK, as I suspected.



It still puzzles me though. An 80 gallon tank, with one small fish in it. Ok, I feed 3-4 times a day, but it really isn't that much protein going into the tank. I'm really surprised that the filters can't cope with it.

I's protein like arowan has said.

3-4 is more than the usual 1-2 times a day.

There are other factors involved.

How long has the tank been established?
Type of bio filtration used ?
Amount of Bio media ?
Established time of bio filtration without being disturbed.

From my experience these protein slicks and slime seem to accumulate when tank conditions are not stable because the bio filtration has in some way been disturbed or properly established. This doesn't mean that your water conditions for your fish are not good for survival, it's just a sign that it is not optimal.

I have found the best way to help counter this is to have more bio filtration than what is required for the size and stocking density of your tank. This gives you overhead to help try keep tank conditions stable.

 

[hamfist]

I's protein like arowan has said.

3-4 is more than the usual 1-2 times a day.

Yes, it is 3-4 times a day, but he's a small, growing fish, and the meals are all really quite small.

There are other factors involved.

How long has the tank been established?
Type of bio filtration used ?
Amount of Bio media ?
Established time of bio filtration without being disturbed.

From my experience these protein slicks and slime seem to accumulate when tank conditions are not stable because the bio filtration has in some way been disturbed or properly established. This doesn't mean that your water conditions for your fish are not good for survival, it's just a sign that it is not optimal.

I have found the best way to help counter this is to have more bio filtration than what is required for the size and stocking density of your tank. This gives you overhead to help try keep tank conditions stable.

What you say makes a lot of sense. However, I still struggle to see how it could be the cause in my tank. The filtration is two good sized canister filters with sponge and ehfimech for mechanical filtration, and at least 3-4 litres of Ehfisubstrat pro between them for bio-filtration. The tank and filters have been set up for many months, and the last time I cleaned out any of the filters was about 2-3 months ago, so no recent disturbance. Both filters seem to still have good flow through them. I gravel vac every couple of days, so the build up of particulate matter in them is also very slow.

However, despite all this, what you say must be true. Protein IS accumulating in my system and either the bio-filtration in my filters is not dealing with it, or it is somehow not getting to that bio-filtration in the first place.
I wonder if somehow the water flow within the tank, and the placement of my filter water intakes is tending to force any proteinaceous gooey matter to the surface, where it stays.

I think the best obvious option is some sort of water skimmer to direct all the slime into a filter. However, it annoys me to have to get one as, logically, I don't think the tank should need one.

 

[slimmer]

Maybe need something to break the water surface and not just move it. Either an air stone from the bottom or a hob breaking the surface from the top.

 

[vfc]

I get the "surface slime" from my tap water. It is there when I fill up a new tank and it never goes away (even in tanks running for years with light bio-load and feeding). I currently have five tank running and all have the slime. It shows within minutes when I power off the skimmers for water changes.

The only solution for me is to keep surface skimmers running all the time. I have skimmers hooked to an XP3, XP4, and Magnum 250.

 

[ar0wan]

...The only solution for me is to keep surface skimmers running all the time. I have skimmers hooked to an XP3, XP4, and Magnum 250.

..and hows that working out for ya

 

[Moloch]

I have slime that clings to my glass canopies and anything else resting over the 2-3 inches of open space behind them (eggcrate, light power-cords, etc) Its definitely brown on the plastic stuff and its a light, slimey almost clear brown on the glass.

Is it the same crap? I don't get slime on the surface on my water, just built up on my glass & other stuff on top of my tank:\