Cloudy Water, do I have a bacterial bloom?



I had a tank in my room, a 10gal, that had been doing well for almost a year. Well, I got a little lazy with the water changes a few months ago and had some issues, mainly with excess algae as it caught a lot of afternoon light. I recently disassembled the tank and thought long and hard about getting rid of it. I kept about a quarter of the original water, all the plants, fish, and sponge filter in a bucket while I was making up my mind, and moved the tank outside for the time being, and I filled it with hose water(temp/weather fair and consistent in my area currently). Well, by the time I rearranged the room and found a better spot for it (about 5 days) I had a huge algal bloom in my tank outside (not really surprised, but a little-- happened so quick) so needless to say I ended up having to do a lot of major cleaning on the tank.

Well, about 5 days ago I got it all set up, and the first two days the fish (4 emerald dwarf rasboras for the time being) seemed happy as clams, brightly colored and very active. Day 3 they seemed stressed; their coloration wasn't as bright. I noticed that in the morning and was wondering if maybe they just spooked as I turned their lights on (have CPDs in another tank that used to do the same thing and give me a heart attack every morning before I got an auto light that gradually turns on) so I went to work and checked on them when I got home-- they were still lacking color. I did a water test and everything appeared to be in the safe zones, so I didn't think much of it. Yesterday, still seemed stressed and swam almost exclusively in the bottom of the tank :/ I was the only supervisor at work so I couldn't/didn't have much time to dedicate to the tank yesterday but thought it was looking cloudy when I left, and my roommate made a comment to me about it when he turned the lights off for me yesterday as I was still at work. This morning I have sadly only have 2 emerald dwarf rasboras now and the tank definitely has a cloud. I have done water tests multiple times this morning with my API kit and still have gotten readings in the clear. I read the manual again to make sure I was performing each of the tests correctly. Thinking on it I have never gotten readings other than base/minimum for any test other than pH so I'm wondering if it's a faulty lot from them (not expired, have 'til 04/2024) so I kept water out after performing a heavy change this morning and am going to have it tested at my local store. I have exclusively used Prime when adding water up until when I reset this tank and I bought and used API Stress Coat+ as I am thinking I will add fish to this tank (once I get it sorted, apparently) and it had advertised reducing fish stress which I was thinking after a being in a few different environments within a short period of time my lil' EDRs may have been experiencing.

I guess my question is this; do we think it's a bacterial bloom? I kept the sponge filter intact from the previous setup and had used the cycled water (about 3 gallons) to boot this new setup so I had figured I would have offset that. How can I help my poor EDR at this point-- I don't want to lose these 2 as well :/

(Note: I added sand substrate that I rinsed thoroughly when I set this tank up again and it was clear for the first few days, so I don't think that has anything to do with it but wanted the info to be included)


I doubt 4 rasboras will foul up 10 gallons in a few days. Any live plants?

What kind of sand? What is your PH?
Where did the Rasboras come from?

If its a bacterial bloom it's hetero trophic. Its not dangerous.
Nitrifying auto trophic bacteria doesn't bloom in the water column. Either way, im not worried about the bloom. Im not worried about the lights.

I think something is up with your water.


Sorry I just now saw this. I checked for responses last night and had no notifications. Came on here to report the two boys I have left have their color back today and are more active.
Exclusively live plants; a giant anubias, and jungle val. Added a few stalks of guppy grass today.
Sand isn’t true sand per se but it was what I could get that was black- I believe it was TopFin brand and I was ultimately not too sure about adding it.
pH I don’t recall. I’ll grab a new sample when I get home tonight.
I did take pics of the cloud and specifically the.. fuzz? I don’t know I can’t tell what’s forming along the one decorative rock I have in there.
The rasboras that are in there I’ve had for 9 months or so in the setup that it had originally been.

EDIT: pH would have been around 6.6 yesterday I believe (had to glance at card again). Also, I had spoken with someone today who thinks I may have killed off the beneficial bacteria in my substrate by letting it sit for 5 days. Thoughts?


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