New 20gal Hex

I set up this 20, with water from my 55 and other 20 that we have. I dunked the new filter cartridge in the bucket with my clean out water.
We stocked it that night with some glo fish- (Sunday), as of last night we have a glo shark and gourami left.

So, my ammonia was around .25, ph 7.8, nitrites were about .25-.50, Nitrates around 20.

When I tested the old tanks today, ammonia and nitrite were 0.
So, why did I get a spike in the new tank?

I didn't have this issue when I set up my daughter's 20- I just took half the water from my 55.
What did I miss?? I did a water change on the new tank this afternoon.

I just found another tetra we missed... its gills look like they were bleeding; what does that?

 

If the gills are v red then it is probably ammonia burns. Did you cycle your aquarium and how many fish did you add on that single day?

 

Taking just water from the other tanks won't cycle it. You need to take filter media from them and put it into the new tanks filter to kick start the cycle.

 

Taking just water from the other tanks won't cycle it. You need to take filter media from them and put it into the new tanks filter to kick start the cycle.

I soaked my media in the water from it...

If the gills are v red then it is probably ammonia burns. Did you cycle your aquarium and how many fish did you add on that single day?

Too many!

 

I soaked my media in the water from it...

Just soaking the media in water isn't the same thing. You want the benecicial bacteria, and 90% lives on the filter media, 9% in the substrate and on decor, and maybe 1% is in the water. So even if you move all the water (not just soak it) to the new tank, you will only be getting about 1% of the bacteria you need. On the other hand, if you have a large chunk of the filter media, you'll be getting lets say 50% depending on the chunk size. As you can see, that is a huge difference.

 

You will need to keep up with large water changes to control the ammonia and nitrites while the tank cycles.

Other members are correct with what they told you. Beneficial bacteria colonizes in the filter media and substrate, not the water column.

Also, cartridges are not very good at colonizing beneficial bacteria and can quickly get clogged with muck.

Here is a LINK I suggest taking a look at for a thread on this forum.

It shows how various examples for adding media to your filter, to boost biological and mechanical filtration while discarding having to use cartridges.

It will help add additional places for the bacteria to colonize.

You will save $$ from not buying disposable cartridges anymore. Plus, when you toss the cartridges and replace it, you've just lost the beneficial bacteria that was cycling your tank.

I would also hold off on adding anymore fish.

Hexagonal tanks are more vertical than horizontal. Fish swim more back and forth, versus up and down.

 

I did the mods on the filter, taking ceramic media from Fluval; a week or so later we put in 3 tetras; two died Friday. Sunday, I upgraded to a Fluval 550 HOB and transferred the media. My husband likes the glo lights on, so I added 2 mystery snails to clean up the algae growth. We also replaced the 2 glo tetras when I changed the filter.
I am hoping this will help...
During this same weekend of loss in his, I lost 2 in my 55 that's been up 1yr. My mom and I are going to break that down tomorrow, remove the undergravel system and redesign. Any suggestions for that?

 

What have your water parameters been like in the 20 gallon hex?

I am not familiar with a Fluval 550. Possibly some additional water changes with a larger volume replaced may be good, after having some fish deaths.

If your breaking down the 55 gallon to redesign it, I would recommend to first consider what your goal for the tank is in the future, as far as stocking and if it will have live plants.

Then base your filtration, substrate and decor on that.

Since you already have a UGF in the 55g, I would also suggest doing a search on the forum for "plenums" and on YouTube look up "Dr. Novak plenum" or "Dr. Novak plenum anoxic filtration".

Plenums/anoxic filtration are used to reduce nitrates.

 

What have your water parameters been like in the 20 gallon hex?

I am not familiar with a Fluval 550. Possibly some additional water changes with a larger volume replaced may be good, after having some fish deaths.

I meant 50, sorry.

For the 55, I am going with eco complete as I want more plants in the tank. So I put my gravel over it, or not? I can't seem to find good info on that.
Is it true that I would not be vacuuming the eco as the plants will use the waste? That was one of my reasons for going with it. I will be keeping my current stock, and maybe adding a small angel.

I did a little research on anoxic- it got a bit too much for me! Are you saying that I should keep the UG? I wanted to remove it, but if it would benefit the substrate, I will keep it.

 

Under gravel filters were never recommended for plants. I would remove it. Ugf collect waste under them which in turn creates problems with water quality. It is recommended to remove them yearly to clean under them. They were some of the first filters. So many better filters out there now.

Eco complete in my opinion does nothing for plant growth. I have it in a 90 and regret putting it in . Even eco will need fertilizers and good lighting to grow plants. After a year or more it becomes a bit of a denitrify filter for a tank. It’s basically crushed lava rock.

 

I can't comment on plants or eco complete. I only have a couple of anubias, and not experienced much with plants.

A plenum would only use the plates of the UGF, and not have water drawn through it.

Your Fluval/Aquaclear 50 should be a good match for the 20 gallon hex tank.