50% water change in the morning. 1.5ml for 10l.Could be Oxygen depletion.
How much water did you change?
What time of day did you do it?
How much Seachem Prime did you dose into the RO/Tapwater?
I know and I have been trying to figure out what is the issue with my tank. Perhaps I may have to reset my tank entirely after the Christmas holidays. Something is certainly wrong with this tank.If it helps I suspect the cooler 50% water change and subsequent fish loss are unrelated in the grand scheme of things. So don't beat yourself up about it.
Looking back at some of your other posts it appears you've already lost a number of pygmy corydoras over the last month or so, certainly before this water change?
Not saying this to be a smart ars#, but suspect either the tank or fish themselves have some underlying issue that's causing the loss, although admittedly I don't know what this could be.
Water tests done showed no ammonia or nitrite spike. I am wondering whether my test kit is faulty. Same water used on my neocaridina tank has no issues whatsoever.That doesn't sound like cold shock to me, the prime symptom I've seen in cold shock is lethargy. My instinct would be either toxin in the added water or toxin in the tank water made more toxic by the water change.
BRJP1 has given the exact advice I would. Test everything to see if there's a hidden problem.
I have tested both my tap and RO water in the past and am familiar with the parametres. TDS about 300-350 ish for tap water and 15 for RO water.@I am Ken - I think there are some good plausible causes here, but it's hard to nail at the moment. As others have mentioned, a 50% water change should not be a problem if all parameters are correct during that change.
As we can't isolate the problem for sure, I can only suggest stepping back and doing some checks at this stage.
I know none of this is an answer, and it could be a temperature issue caused by the change, but I would just take stock of the environment right now and check if anything comes to light.
- Test the water for basics to understand where you are right now (Ammonia, Nitrite, Nitrate, Chlorine, TDS, Temp ) and record that somewhere.
- I would also test both your raw tap water and RO water for Ammonia, Nitrite, Nitrate, Chlorine and TDS to understand the readings at the source.
- It looks like you have a sponge filter and assume that is working? Keep that running, and only clean it when it's clogged to let any bacteria build up. (i.e. let's not remove any goodness by over-cleaning).
- I can't tell if it's the camera image due to light, but there is a certain amount of milky haze in the water - is that the camera light or is it crystal clear in reality?
- Check/increase the aeration by upping surface agitation or enough air bubbles to create that agitation.
- Stick your finger (gently to not disturb too much but enough to 'coat' your finger) into the gravel and give it a sniff test to check that it does not smell eggy or sewage-like.
Interesting.Yes, water was slightly milky.
And this.I then cleaned my HOB filter and did a water change, and this happened. I am wondering about ammonia in the gravel since I used the gravel vacuum to clean it, but that should improve the water quality not worsen it.
Used tank water.Interesting.
So, you may have a lot of bacteria in the water column. i.e. enough bacteria build up in the water column that you can see it. The Ammonia to Nitrate cycle is much easier to achieve than crystal-clear water.
To round this off:
- How often do you clean your Sponge Filter?
- How do you clean your Sponge Filter? (i.e. under tap water, in tank water).
Yes, I actually just added activated carbon to my hob filter a few days ago.And this.
Is it possible you did a water change, cleaned the Sponge Filters, cleaned the HOB Filter and the Gravel in short timescales?
50% water change in the morning. 1.5ml for 10l.Could be Oxygen depletion.
How much water did you change?
What time of day did you do it?
How much Seachem Prime did you dose into the RO/Tapwater?
Wrong! Very wrong you are. Vacuuming is dangerous because you release whatever is buried in the sediment.I am wondering about ammonia in the gravel since I used the gravel vacuum to clean it, but that should improve the water quality not worsen it.
That gravel cleaning could be part of the chain of events that resulted in the loses!Wrong! Very wrong you are. Vacuuming is dangerous because you release whatever is buried in the sediment.
The sediment is not oxygenated and its redox is negative. If you disturb it, unexpected actions and re-actions occur.
50% water change in the morning. 1.5ml for 10l.
Seachem Prime should be dosed at 1.25ml per 50 Litres......if you did a 50% water change, of that water being 50% RO.
That would mean you have added 5 litres of Tap water dosing 1.5ml Seachem Prime.
That could possibly be the answer.....doing the water change in the morning when the aquarium would be low in Oxygen is part of the puzzle.
The Prime dosage could have done unrepairable damage and distressed the Corys resulting in their demise.
It's an old common observation that doing all maintenance at once is not recommendable. Both the sediment and filter are environments which mature and develop some kind of equilibrium. If you disturb any of them, stability is lost. It seems, though, that the other part is often capable of saving the day if left undisturbed.So what do I do now? Do I create a bare bottom tank then or what substrate should I do?
I've cancelled all biological filtration in my tanks. I don't expect you'll follow my example. People are getting good results with mechanical pre-filters. These keep the filter itself free of excess dirt and you can leave it untouched for long time, easily several months. You only regularly clean the pre-filter.
I think that is an excellent question/point to raise. And I should explain my personal reasons - especially as I have asserted my view on someone else without qualification/detail.The situation in this tank is unusual because there are no plants/very few plants in the substrate. An extensive plant root system actually helps to prevent build up of nasty toxins.
I would add, so does regularly vacuuming of the substrate if you do it regularly, how could there be an opportunity for the H2S to build up?) On the other hand, if you do haven't vacuumed the substrate for many months and then decide to do so, there might be danger.
I regularly vacuum the substrate every 3 weeks with no issues to my Corydoras, but I have plants with extensive root systems in the substrate as well.
I’d personally use sand. Corydoras ideally need sand to exhibit natural behaviour of digging and sand sifting. Gravel doesn’t allow this and I wouldn’t keep corydoras on anything other than sand, it’s not fair on the fish in my opinion.What the hell? So I have to watch out for Prime overdose and avoid vacuuming the gravel as well?
So what do I do now? Do I create a bare bottom tank then or what substrate should I do?
It looks like this but I believe the reality is different.Gravel also traps a massive amount of detritus and waste. This doesn’t happen with sand as the waste simply sits on top where it can easily be siphoned away.
I agree with the other posters. Have a sand substrate and <"leave it relatively undisturbed">?So what do I do now? Do I create a bare bottom tank then or what substrate should I do?
that’s interesting, it doesn’t seem to be the case in my tanks. However, every tank has corydoras in it and also Malaysian trumpet snails so I’m sure they both do a good job of shifting the detritus up into the water column to be removed by mechanical filtration.In my tanks with soft sand there's no detritus on the surface but lots of it appear when I touch the substrate