Blue-green algae & substrate change.

[Cathyplus2]

Hi all,

To say that I was gutted to spot the blue-green algae would be an understatement, but hey-ho, these things are sent to challenge us I guess.

My 60l tank has been going well since Jan 20, the cycling went perfectly and I was very cautious and went very slowly before adding fish. Everything was going swimmingly until I spotted the blue-green menace.

After a 50% water change, vacuuming and removing all I could find, I have tried 4 days of blanket-covered darkness, but when the blanket was removed there were new signs of the bloomin' stuff 

I am now thinking about doing a complete substrate switch - at the moment I have got 1/3 sand 2/3 gravel and the sand is a bit of a nightmare to keep clean, so I am guessing this might be the culprit. I also want to replace a couple of the bits of decor, to improve the flow and cleaning accessibility.

My starter plan is to put new substrate into treated water for 2-3 days, along with some new plants and decor. Then on the big day my plan is to siphon water out of the tank into a holding bucket, put in the filter & heater and then the fish. Then remove all existing substrate, clean every sign of blue-green algae, then re-build tank, add in the treated water, new decor & plants. Then acclimate the fish, rinse the filter in the old water siphoned from the tank and then add back into the tank. I was then going to do a 20% water change + treatment every couple of days, whilst testing/monitoring the levels.

What do people think - I don't have a separate holding tank, so I'm a bit limited about the process, but I need to permenantly get rid of the blue-green algae and want to generally improve the long term health of my fish/tank, so that I don't have any further problems. I am also a bit nervous about adding the filter back into the newly set up tank, in case there is blue-green algae lurking somewhere - what do people think?

Any advice would be most welcome.

Thanks LOADS,

Cathy

[TropicalFishForums]

[mattindevon]

My tank developed some blue-green a few months after replacing gravel with sand substrate. This particular algae was all sat on the top of plants near/at the surface so light must be something to do with it. Said plants were recently gardened and now they are nowhere near the surface the problem has gone. Your situation sounds difficult. Are there any fish that eat the stuff I wonder? The algae in my tank was too high for my Siamese algae eater to find so I couldn't try it on him.

[Cathyplus2]

Hi Matt,

I've got a Betta, some Ember Tetras, some Pygmy Corys and a few Nerite Snails. The Corys pootle about having a bit of a clean-up and the snails do a great job; I think the problem is that it's a bit crowded with decor and the sand/gravel mix isn't working.

I do regular water changes and vacuuming, but the vacuuming is only really possible for the gravel, as it just sucks the sand straight up and blocks everything!!

I've started treating with Easy Life Blue Exit (which I hate, as I didn't want to use chemicals), but I am hoping to get rid of the cyanobacteria, let the tank rest and then put my change of substrate & decor into practice.

All of my little dudes seem quite happy swimming around, but I just want to make sure that they stay that way!

How do you manage to clean your sand, or have you found a vacuum that works?

Thanks loads,
Cathy

[mattindevon]

I've used Tana sand, which has a heavy-ish grain and it easy to vacuum as none of it gets sucked up if I'm careful. The usual fine sand is very difficult in comparison. It doesn't appear to be too dirty below the surface, in which I suspect the corys have a part to play. The loaches aren't averse to a bit of bottom dwelling either.

Sorry, I'm not an expert and can't offer you much advice as such but thought I'd share what little I do know.