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Reviving or Rebuilding Algae-Infested Tank

PostPosted: Sat Jan 07, 2017 10:34 pm
by rlcochran

My name is Bob Cochran. I'm the same person as user "BobCochran" who posted to this forum a few years ago, and then dropped off from posting. I tried to get a new password for my BobCochran user account, but had difficulty with that. So, I've set up a new user name. If this is against forum policy please let me know. I will honor forum policy.

When I left off, I had a 27 gallon cube fresh water tank which had plenty of fish in it but was experiencing heavy algae growth. The issue was actually placement of the tank. It was just way too close to a very sunny dining room window. That kept the algae going to this very day. Due to a mistake that I made, there was also a snail infestation. The snail armies kept coming in almost endless waves. The tank is still in that location. I had lots of baby fish, mostly red wag platies, but not all the babies were red in color. Some were yellow. A lot of these babies (the ones which survived their parents) were transferred to outdoor fish tubs and thrived there. The indoor fish stayed, and one by one they died. The snails also died off, but it took a long time for the last of them to go.

Today the last fish, a yellow colored offspring of a red wag platie, died. So I have a tank full of water, plants infested with hair algae, and plenty of other algae on the tank walls and carpeted on the substrate. I stopped using the Filstar XP-1 filter a long time ago -- more than a year ago -- but I've neglected the filter, and never dismantled it or did any kind of service on the XP-1 since unplugging it from the electrical supply.

What I want to do is to restock this tank with fish. I want to move the tank to a better location in the house and restock it. How should I approach this? Should I totally clean out the interior of the tank: remove and toss all the water and substrate and plants, wash the interior really well, and then cycle the tank again as if it were brand new? Or should I try to keep the current water and substrate since the tank is cycled, but do my best to clean out the inside? Note that I have not recently tested the tank water for things like ammonia. I suppose the XP-1 filter will have to be replaced entirely with a new one.

Let me see...I think, as user "BobCochran", I also discussed something with C. Andrew Nelson via "private messages", but I never followed up, something I'm a bit ashamed about. C. Andrew, if you are still around the forum, perhaps we ought to revive that conversation.

Thanks for any advice you can give me about my tank.


Bob Cochran

Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Sat Jan 07, 2017 10:43 pm
by lucasgg
Id keep the substrate and plants, but clean the substrate throughly with tap water and then rinse out the tap water with purified or de-chlorinated water. Make sure the plants and algae free. Throughly clean the entirety of the filter but don't purge the beneficial bacteria. Aka use dechlorinated or purified water. Please post pics

Sent from my iPhone using Tapatalk

Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Sun Jan 08, 2017 9:47 am
by Crazygar
Personally, if you have no other fish left in the tank, throw everything out (water, substrate, plants, decor) and clean the filter very well along with the tank.

Replace the media in the filter (throw out sponges, media currently in the filter) and find the location you want. Less hassle in the long run.


Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Sun Jan 08, 2017 9:54 am
by rlcochran

Thank you for getting back to me. Here are two photos of the tank. Yes, it is quite neglected. I plan to move it to a location where it will be easier for me to take care of it.





Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Sun Jan 08, 2017 1:43 pm
by Diana
You can try the 'One Two Punch' method of algae control. This is a strong dose of H2O2 followed by a strong dose of Excel. Lets see if I can find it.
... ... tment.html

A filter that has been closed up can grow anaerobic bacteria. Open it up outside. If it stinks, then you could try running a strong dose of H2O2 or bleach through it (or one, followed by the other, with thorough rinsing in between).

Get more plants. The amount I currently see in the picture is not enough to use up the nutrients.

Get some Zebra Loaches to kill the snails. If you keep existing materials (especially substrate) there will be no way to get rid of the snails. Anything toxic to snails (like copper) are also toxic to the fish.

Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Sun Jan 08, 2017 2:24 pm
by rlcochran
Thank you, Diana! I assume that by "H2O2" you mean the liquid hydrogen peroxide which can be bought at any pharmacy or store with a first aid counter. "H2O2" is not a brand name, but Excel is -- it is a product I get at my local fish store, right? Thanks. I'm a bit ignorant.

Thanks a ton


Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Sun Jan 08, 2017 2:34 pm
by ScottFish
Welcome back Bob!

Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Sun Jan 08, 2017 5:48 pm
by C. Andrew Nelson
Good to have you back, Bob. (Yep, I'm still here!)

I was thinking the same thing as Gary. Clear it all out and start fresh like you would a new tank. As for the plants, see if they are salvageable. Maybe you can rid them of algae without damaging them too much.

Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Sun Jan 08, 2017 6:55 pm
by rlcochran
Hi Andrew! Thank you for the welcome. And I am starting to agree that tossing everything out and starting fresh is a good idea. I do need spouse approval to move my tank elsewhere. That is the tricky part.


Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Mon Jan 09, 2017 7:31 am
by Crazygar
Sometimes, tanks just materialize in new locations. Used to happen to me all the time. LOL


Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Mon Jan 09, 2017 10:51 am
by Diana
H2O2 is the common Hydrogen Peroxide available at most stores in the USA, 3%.
If you use some other dilution you will have to do some math to figure out how much to use. I know stronger dilutions are available, for example at medical supply specialty stores.
I know H2O2 is also available in other countries, but I do not know which dilution it is.

Yes, Excel is the Seachem product, gluteraldehyde is the active ingredient. Similar comment as the H2O2- if you are using a different source of gluteraldehyde, then do the math so you get the dilution correct.

Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Mon Jan 09, 2017 2:09 pm
by Crazygar
Looking at the state of the tank though, I believe a total nuke and restart would be in order. It would be less work and it'll give you the opportunity to change a few things in the process.


Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Tue Jan 10, 2017 1:21 pm
by Diana
Yes, redoing the whole tank is probably better in this case, but anything you reuse may bring the algae back. Killing this crop of algae on the materials and equipment will at least give a head start with a low algae count. But algae will grow back. Algae spores are all around. Given the right setting, they will grow. Here is a way to minimize this:

Work with this tank the way it is, or tear it down, whichever you want.
1) Kill off the existing algae.
a) If you are keeping the existing plants and biofilter, then you cannot use chlorine or most other things to kill off the algae. Plants and filter media can hold onto bits of algae so the algae can regrow. One-Two Punch kills algae, but can seriously compromise the biofilter. But with no fish this is not an issue. The tank will not support nitrifying bacteria anyway, without a source of ammonia.
b) If you tear down everything, throw away the plants, then you can bleach everything that can tolerate bleach. This will kill the algae, and pretty much everything else, then some rinsing in water with dechlor will remove the bleach. Chlorine evaporates, too, so just air drying everything will remove the chlorine, too.
2) Add more plants (New 'scape is OK, too). Treat incoming plants to minimize algae. A dip can help.
3) Keep working with nutrients, light and CO2 until you get it figured out. What balance will work for you in this situation? What maintenance is needed to keep the algae to a minimum? You might end up trying several solutions before settling on something that works for you. If light from the window is too much, then maybe you need to put a back on the tank- paint it, or add a background, or hang a sheer curtain at the window to cut a lot of the light.
4) One of your questions in the first post was how to cycle the tank, without the fish. Here is the fishless cycle (below the line). While you are working out the details in part 3) you can also do the fishless cycle.
5) Restock with fish.
Cycle: To grow the beneficial bacteria that remove ammonia and nitrite from the aquarium.

Fish-In Cycle: To expose fish to toxins while using them as the source of ammonia to grow nitrogen cycle bacteria. Exposure to ammonia burns the gills and other soft tissue, stresses the fish and lowers their immunity. Exposure to nitrite makes the blood unable to carry oxygen. Research methemoglobinemia for details.

Fishless Cycle: The safe way to grow more bacteria, faster, in an aquarium, pond or riparium.

The method I give here was developed by 2 scientists who wanted to quickly grow enough bacteria to fully stock a tank all at one time, with no plants helping, and overstock it as is common with Rift Lake Cichlid tanks.

1a) Set up the tank and all the equipment. You can plant if you want. Include the proper dose of dechlorinator with the water.
Optimum water chemistry:
GH and KH above 3 German degrees of hardness. A lot harder is just fine.
pH above 7, and into the mid 8s is just fine. (7.5-8 seems to be optimum)
Temperature in the upper 70s F (mid 20s C) is good. Higher (to 95*F or about 35*C) is OK if the water is well aerated.
A trace of other minerals may help. Usually this comes in with the water, but if you have a pinch of KH2PO4, and trace elements like CSM+B that may be helpful.
High oxygen level. Make sure the filter and power heads are running well. Plenty of water circulation.
No toxins in the tank. If you washed the tank, or any part of the system with any sort of cleanser, soap, detergent, bleach or anything else make sure it is well rinsed. Do not put your hands in the tank when you are wearing any sort of cosmetics, perfume or hand lotion. No fish medicines of any sort.
A trace of salt (sodium chloride) is OK, but not required.
This method of growing bacteria will work in a marine system, too. The species of bacteria are different.

1b) Optional: Add any source of the bacteria that you are growing to seed the tank. Cycled media from a healthy tank is good. Decor or some gravel from a cycled tank is OK. Live plants or plastic are OK. I have even heard of the right bacteria growing in the bio film found on driftwood. (So if you have been soaking some driftwood in preparation to adding it to the tank, go ahead and put it into the tank) Bottled bacteria is great, but only if it contains Nitrospira species of bacteria. Read the label and do not waste your money on anything else.
At the time this was written the right species could be found in:
Dr. Tims One and Only
Tetra Safe Start
Microbe Lift Nite Out II
...and perhaps others.
You do not have to jump start the cycle. The right species of bacteria are all around, and will find the tank pretty fast.

2) Add ammonia until the test reads 5 ppm. This ammonia is the cheapest you can find. No surfactants, no perfumes. Read the fine print. This is often found at discount stores like Dollar Tree, or hardware stores like Ace. You could also use a dead shrimp from the grocery store, or fish food. Protein breaks down to become ammonia. You do not have good control over the ammonia level, though.
Some substrates release ammonia when they are submerged for the first time. Monitor the level and do enough water changes to keep the ammonia at the levels detailed below.

3) Test daily. For the first few days not much will happen, but the bacteria that remove ammonia are getting started. Finally the ammonia starts to drop. Add a little more, once a day, to test 5 ppm.

4) Test for nitrite. A day or so after the ammonia starts to drop the nitrite will show up. When it does, allow the ammonia to drop to 3 ppm.

5) Test daily. Add ammonia to 3 ppm once a day. If the nitrite or ammonia go to 5 ppm do a water change to get these lower. The ammonia removing species and the nitrite removing species (Nitrospira) do not do well when the ammonia or nitrite are over 5 ppm.

6) When the ammonia and nitrite both hit zero 24 hours after you have added the ammonia the cycle is done. You can challenge the bacteria by adding a bit more than 3 ppm ammonia, and it should be able to handle that, too, within 24 hours.

7) Now test the nitrate. Probably sky high!
Do as big a water change as needed to lower the nitrate until it is safe for fish. Certainly well under 20, and a lot lower is better. This may call for more than one water change, and up to 100% water change is not a problem. Remember the dechlor!
If you will be stocking right away (within 24 hours) no need to add more ammonia. If stocking will be delayed keep feeding the bacteria by adding ammonia to 3 ppm once a day. You will need to do another water change right before adding the fish.

Helpful hints:

A) You can run a fishless cycle in a bucket to grow bacteria on almost any filter media like bio balls, sponges, ceramic bio noodles, lava rock or Matala mats. Simply set up any sort of water circulation such as a fountain pump or air bubbler and add the media to the bucket. Follow the directions for the fishless cycle. When the cycle is done add the media to the filter. I have run a canister filter in a bucket and done the fishless cycle.

B) The nitrogen cycle bacteria will live under a wide range of conditions and bounce back from minor set backs. By following the set up suggestions in part 1a) you are setting up optimum conditions for fastest reproduction and growth.
GH and KH can be as low as 1 degree, but watch it! These bacteria may use the carbon in carbonates, and if it is all used up (KH = 0) the bacteria may die off. They use the carbon from CO2, and this is generally pretty low in water, but can be replenished from the air and from carbonates. Keep the carbonates up to keep the pH up, too.
pH as low as 6.5 is OK, but by 6.0 the bacteria are not going to be doing very well. They are still there, and will recover pretty well when conditions get better. To grow them at optimum rates, keep the pH on the alkaline side of neutral.
Temperature almost to freezing is OK, but they must not freeze, and they are not very active at all. They do survive in a pond, but they are slow to warm up and get going in the spring. This is where you might need to grow some in a bucket in a warm place and supplement the pond population. Too warm is not good, either. Tropical or room temperature tank temperatures are best. (68 to 85*F or 20 to 28*C)
Moderate oxygen can be tolerated for a while. However, to remove lots of ammonia and nitrite these bacteria must have oxygen. They turn one into the other by adding oxygen. If you must stop running the filter for an hour or so, no problem. If longer, remove the media and keep it where it will get more oxygen.
Once the bacteria are established they can tolerate some fish medicines. This is because they live in a complex film called Bio film on all the surfaces in the filter and the tank. Medicines do not enter the bio film well.
These bacteria do not need to live under water. They do just fine in a humid location. They live in healthy garden soil, as well as wet locations.

C) Planted tanks may not tolerate 3 ppm or 5 ppm ammonia. It is possible to cycle the tank at lower levels of ammonia so the plants do not get ammonia burn. Add ammonia to only 1 ppm, but test twice a day, and add ammonia as needed to keep it at 1 ppm. The plants are also part of the bio filter, and you may be able to add the fish sooner, if the plants are thriving. 1 ppm twice a day will grow almost as much bacteria as 3 ppm once a day.

Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Tue Jan 10, 2017 6:22 pm
by rlcochran
Thank you so much, Gary and Diana! I'm going to start completely fresh with this tank. I'll work to kill the algae, and get rid of the substrate, plants, Filstar XP-1 and sponge filter. I need spouse permission to move the tank somewhere else. I will see what evolves.

Thanks a ton!


Re: Reviving or Rebuilding Algae-Infested Tank

PostPosted: Wed Jan 11, 2017 7:32 am
by Crazygar
Glad we all could help! Keep us updated on your progress.