Often times we see the new diver tackle on a brand new adventure with a boat anchor tied to their tanks.
I'm kidding, although I did once watch the owner of a dive center pull a small anchor out from behind the counter and hand it to a customer who claimed he needed more weight to stay down during their stops while ascending on a dive.
In reality, it is often the opposite. You see, in order to maintain neutral buoyancy while diving, we have to compensate for the weight we carry by adding gas SOMEWHERE. That "somewhere" might be either your wing or dry suit, and because that gas is there it will expand on ascent. All certified divers are taught this principle during their open water course. Divers are also taught that the rate of expansion nearer to the surface is more significant - if there is an excess of gas in your suit or wing, it will expand at a faster rate than a minimal amount of gas, thus making it more difficult to stay at depth. The more weight you have to compensate for, the more the buoyancy swing calls for adjustments.
Ever seen those videos where a diver inflates a balloon at the bottom of a pool? If you took two balloons, one filled more than the other, you would find that the fuller balloon expands faster and to a larger volume. The same happens with your gear. The shallower your depth, the more pronounced that change becomes when trying to hold those shallow stops.
Having a hard time keeping your stops during your ascent? It might be because you're too heavy, not too light.