Algae bloom

[michaelwgroves]

I have a 1000L planted tank, CO injection, feed plants daily, 12 hours of light, nothing changed in last year.
However, I've been struggling with the amount of time I have to spend every week pruning plants, so I decided to stop feeding. This helped a lot with maintenance. I then decide to remove some old very well established plants as they were blocking light to substrate.
I thought I would then restart feeding at 50%.
Within 3 days the tank has an algae bloom. I stopped plant feeding, reduced light, and started 20% water changes 2-3 times a week. After 3 weeks there is no improvement. I've now decided to feed plants as per previous doses and lights back to 12 hours. in a hope with vigorous plant growth will see off algae. I also guessed it might be phosphates, so bought every phosphate filter you can buy for my Fluval FX5. Then bought tester, but apparently I have no phosphates, 0 nitrates and 0 nitrite. Stocking levels are low

I'm on day 4 of phosphates filters and normal lights/plant feeding, but no difference. It's dual aspect tank, and I can't see through it. I also use polishing pad for max filtration.

I'm lost for idea's, any thoughts?

Thanks,

 

[Colin_T]

Pictures of the tank and algae so we know what type it is?

If you are concerned about phosphates in the tank, just do a massive (90%) water change to dilute any nutrients in the tank and fertilise after that.

You probably won't get any ammonia, nitrite or nitrate in a heavily planted tank with fast growing plants due to the plants sucking up the ammonia. If there's no ammonia there won't be any nitrite or nitrate.

 

[Rusty_Shackleford]

Is it green water ie, single celled free floating algae you're having an issue with, or algae on plants, glass etc?

 

[michaelwgroves]

It’s free floating particles, glass is clean.

 

[Rusty_Shackleford]

It’s free floating particles, glass is clean.
View attachment 372248

OK this is an easy one. Get yourself a UV clarifier/sterilizer. It will clear that tank in 7-10 days tops.
I went through the same thing myself earlier this spring. My cause was getting new lights and having the lights too bright. I tried everything, I stopped using fertilizer, blacked out the tank for a week, 50% water changes every other day. What worked was the UV.
Now you still need to find the cause of why. In your case it may be that you stopped fertilizing which made your plants weaker. Plants like things very consistent. I find when you change in a plants routine like light or fertilizing there is some sort of reaction in response to those conditions.

Edit: Check this out. Feel free to look at the whole thread.
Post in thread 'Aquatop SP7-UV Submersible UV Filter' https://www.fishforums.net/threads/aquatop-sp7-uv-submersible-uv-filter.496924/post-4366008

 

[michaelwgroves]

Thanks for suggestions, I've read the other post. I'm in UK so can't get US products.
I've ordered Fluval inline filter as this works for up to 1500L tank. I'll let you know how I get on. Hopefully I can fit this weekend

 

[Colin_T]

It's green water caused by single celled algae. Reducing light and nutrients usually gets rid of it. Try doing a massive water change each day for a couple of days and reduce the light by an hour a day, then see how it goes over the next week or two. Cut the fertiliser back to half strength for a couple of weeks. The combination of that should get rid of it.

If the light has different intensity settings you can reduce that by 10-20% instead of reducing the day length by an hour.

You can also put a fine filter pad in the filter to trap it but you will need to clean the pad regularly until it's gone.

 

[michaelwgroves]

I was talking to a friend, 24 hours before the breakout I removed a big established plant which exposed a lot of the substrate, he thinks this could have been the cause of the out break.
I've also noticed big PH swings from 6.5 to 7.0 over night. My CO dosing pump keeps it below 7.0 but now it just drops down as low as 6.6 overnight.

I always run fine filter, I'll keep water changes going until it's gone. I read algae runs out of steam naturally around a month. So I'm wondering if my UV will be too late, and it will go on it's own anyway ?

 

[Colin_T]

This was probably caused by you removing some plants. You had a nicely balanced system that used all the light and nutrients you provided. Then you removed some plants and now there is too much light and too many nutrients for the remaining plants to use. When this happens and you get an imbalance in the system, algae grows.

In the wild green water (single celled algae) can come and go throughout the year (it usually appears in spring or early summer when there are lots of nutrients that have built up over winter, and there is long fine sunny days. In the wild green water can last a few weeks to a few months and usually goes away once the nutrients have been used up. However, in an aquarium where you have a nice steady lighting schedule and are constantly supplying nutrients, the green water can last permanently. Breaking the supply chain by removing the nutrients or reducing the light, will usually break the cycle and stop the algae flourishing.

If you had baby fish you could put them in the tank and they would do really well feeding on the algae and other micro-organisms in the water

A UV steriliser will definitely help with this type of algae so if it doesn't go after a few water changes and reducing light and nutrients, then the UV unit should get rid of it pretty quickly (within a few days).

 

[michaelwgroves]

Thanks for details, it helps to understand what happened, I'll let you know how I get on

 

[michaelwgroves]

Fluval UVC installed yesterday, 24 hours later and I don't see any change
I hope tomorrow brings better news.......

 

[Colin_T]

Try to slow the flow rate of water going through the UV unit. The longer the water is exposed to the UV light, the faster it will kill them. Then just wait and see how it goes. If it hasn't cleared it in a week, then the UV unit may be dodgy.

 

[michaelwgroves]

UV unit has 1" pipe, on install I reduced to 1/2".
Maybe I need to be less impatient...........

 

[michaelwgroves]

Day 3 no different

I've maintained lights and plant feeding in an effort to get plants to grow to absorb nutriants.
Do you think RO water changes would help, I've just been using tap water ?

 

[Colin_T]

Tap water is fine for water changes, as long as it's free of chlorine/ chloramine.

Silly question from me, but is the UV unit turned on?
It probably is but I just have to ask.

Can you slow the flow rate down by putting a smaller water pump on the UV unit?

Normally a UV unit will start to make a noticeable difference within 24-48 hours and there's a massive improvement after a week. If the UV unit isn't working, you could add some live Daphnia. They feed on single celled algae and might help to clear it up over a few weeks. You would have to put a sponge on the intake of any power filters so you don't suck them up but if they don't get eaten they would breed prolifically and eat the algae. Then you could scoop them out and give them away or freeze them for use later on.