Bacteria bloom?

[Netsirk203]

Since you've come to the emergency forum, we know you want a fast answer to your question. In order for us to figure out the problem as quickly as possible, we ask that you answer the following questions as best you can. Some of them may seem odd, but they're all designed to give us the information we need to give you a good solution for your problem. The things in the [ brackets ] are there to make this post easier to read once submitted. Thanks!


1. What kind of substrate is used in your tank and how deep is it?
50/50 play sand and EE. 6-8 inches deep

2. Do you have gauges in the tank to measure temperature and humidity? If so, where are they located and what temperature and humidity do they usually read?
Yes near top of tank, not sure... Husband has been caring for them and now handing them off to me. We're currently in the middle of relocating tank so can't give current readings. I want to say humidity is usually in the 75-85% range and temp is 75-80.

3. Is a heat source used in the tank? If so, what?
Yes, multiple of the flat pads attached to back of tank.

4. What types of water are available (fresh or salt) and how is the water treated (what brands of dechlorinator or salt mix and what ratio is used to mix it)?
Both are provided. Aquarium salt is used for the salt water.

5. What kinds of food do you feed and how often is it replaced?
Variety of dried foods made specifically for crabs that I purchase on ebay plus fresh fruits/veggies. Changed every few days.

6. How long have you had the crab and what species is it, if known?
We have 5 crabs we've had for 2 years. One that is reddish in color, the others are purple.

7. Has your crab molted, and how long ago did it happen?
They've all molted numerous times, been a few months but they're pretty big.

8. What type of housing are the crabs kept in, what size is it and what kind of lid is on the housing?
Kept in a tank that's maybe 50 gallons has a glass lid that we leave cracked to keep humidity levels where they need to be.

9. How many crabs are in the tank and about how large are they?
5 crabs in approximately 1" shells

10. How many extra shells are usually kept in the tank, if any?
5-7 extra shells right now. Having trouble finding the right sizes shells for them.

11. Have there been any fumes or chemicals near the crabitat recently?
No

12. How often do you clean the tank and how?
Clean top layer every couple months and clean up food as needed.

13. Are sponges used in the water dish? If so, how are they cleaned?
No.

14. Has anything new been added to your crabitat recently?
No.

15. Is there any other information you would like to share that might be helpful (anything that is regularly part of your crab care, playtime, bathing, etc.)?
No

16. Please describe the emergency situation in detail.
My husband moved our crabs to a basement location a few months ago and today we are moving it back upstairs. When pulling out the substrate so we could lift the tank a strong rotten egg smell filled the house, but the substrate smells and looks normal. Nothing growing. It no longer smells now that we've emptied it all out. Was it just a pocket of something or could this be a bacterial bloom? What do I need to do? Is it safe to put the crabs back in?

.

[DragonsFly]

Sounds like you may have hit a pocket of gas from decomposition of something, but if it were me, since you emptied it out already anyway, I'd clean the inside of the tank well with vinegar and water, dry thoroughly, and then (out of an abundance of caution) probably start with new substrate, if you can afford to do so. Warming the water you use to moisten the substrate will make it quicker to get the tank back up to the proper temp and humidity. Best wishes!

[wodesorel]

I agree with DragonsFly, if you're that far into a teardown already, I would be starting with fresh substrate. It should be okay just having mixed it up and exposing everything to air, but I don't like to take the chance with my own crabs if I have the option. Lugging home that much sand might not be a possibility though! The egg smell was definitely bacterial growth and decay of some sort, though.

[Netsirk203]

Ok thanks, didn't have stuff in hand so went ahead and put the old stuff back in. Gonna keep an eye (nose) on it and will do a full substrate change if I notice any odor.

[DragonsFly]

The problem is that (remember) you did not smell the odor until you disturbed the substrate; so just sniffing every now and then may not reveal if there is a bacterial bloom going on underneath. But if you have any crabs down, you don't want to just go randomly digging down to the bottom of the tank here and there, either (even if you know where they started to go down on the surface, you can never tell where they will end up down below). So. . . at this point, just be very careful about not allowing water to pool or substrate to get too compacted; and take extra care with where food bits end up. For example, I gave mine a shrimp tail a little while ago; it was immediately grabbed and dragged under something, where they enjoyed it immensely for hours--but I made sure to find it the next day and get it out of there before it started to rot. I'm sure they thought I was a party pooper, and might have enjoyed it further the following night, but they live in a very confined space, and I want to keep it as healthy for them as possible, so I made sure to find the remains of the shrimp tail before it got dragged elsewhere and/or buried to just become a bacterial hazard.