dragon poop should consist of a formed elongated mass..with a smaller opaque chalk like section which typically is white or off white, clear mucus or fluid typically is also present. It will be easy to tell a cigar or cylinder shape in the poop...which typically is brown..usually dark brown...though color can vary depending on what is being fed.
For a 4 month old dragon, especially if he is less than 14" long (snout to tail tip) I recommend getting rid of all the sand. Use paper towel, newsprint, non stick shelf liner and other non particulate substrates instead. For dragons 14" or longer regular washed and sifted children's play sand can be used...I personally think the non particulate substrates are best.
For paper towels, newsprint type substrates, spot clean by removing the soiled substrate, washing underneath if it appears to have soaked through with a mild anti-bacterial cleaner (with no bleach, or ammonia...anti-bacterial soap and a damp cloth works fine). Do this as soon as you see soiled substrate. With young dragons it may be a few times a day. Spot clean non stick shelf liner etc. Total cage wash should occur once a month.
Sand..scoop out the solid waste daily. Look closely for poop as dragons can easily bury it and it will go unnoticed. Change out the sand completely every month.
I recommend not handling your dragon the first week or two at all. Wait till he is eating regularly and comfortable with you outside the cage and him inside. You can talk to it or simply watch him when he is basking etc. Avoid sudden movements which could startle your dragon and make him hide.
Food and water dishes should be washed daily. Always wash dishes and items used in a reptile's cage separate from your own 'people' dishes. A separate sink should be used...or at the very least, wash pet dishes and items after the household dishes are washed and the sink disinfected with bleach. Separate sink is best.
There are many products that can be used but for water dishes and food dishes I just use standard anti-bacterial soap, the liquid or gel kind, smear all over the bowl, sit for about ten minutes and rinse completely.
For disinfecting cage furniture, especially wood or large pieces, a bleach solution or a product like Novesan(I think its called) mixed according to directions (comes in a concentrate...I never use it myself mostly because can't seem to find it around here. But typically one part novesan to 50 parts water...which is strong enough to disinfect cages etc.) For bleach, one part bleach to 100 parts water, though when cleaning after treating a sick dragon, or for parasites...I use a 1:10 bleach/water ratio. Soak for 20 minutes, rinse very well, especially with the stronger solution. Air dry in a ventilated area...outside is best.
Typically though, washing with an antibiotic cleaner with a cloth the entire interior of a cage once every couple months is sufficient to ensure your pet remains healthy. Twice yearly a full disinfect should be done.. the monthly ones can be more washing the bottom of the cage with a diluted cleaner/disinfectant.
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PHLdyPayne